EXHIBIT 99.11
                                                            [EXHIBIT 5.15(a)(i)]

                                                                  EXECUTION COPY

      Comcast Corporation                    Adelphia Communications Corporation
       1500 Market Street                             5619 DTC Parkway
     Philadelphia, PA 19102                      Greenwood Village, CO 80111

                                              April 20, 2005

Time Warner NY Cable LLC
c/o Time Warner Cable Inc.
290 Harbor Drive
Stamford, CT 06902-6732

      1. Introduction. This letter agreement (this "Agreement") confirms the
agreement of Time Warner NY Cable LLC ("Buyer"), a Delaware limited liability
company and an indirectly wholly owned subsidiary of Time Warner Cable Inc.
("Parent"), a Delaware corporation, Adelphia Communications Corporation, a
Delaware corporation ("Seller"), and Comcast Corporation, a Pennsylvania
corporation ("Comcast"). Capitalized terms used but not otherwise defined herein
shall have the respective meanings ascribed to them in the Comcast Purchase
Agreement (as defined below).

      2. Joint Acquisition of Seller and Asset Purchase Agreements. Seller and
certain of its Affiliates have filed voluntary petitions for reorganization
under chapter 11 of the United States Bankruptcy Code and are currently subject
to chapter 11 proceedings in the United States Bankruptcy Court for the Southern
District of New York. Contemporaneously with the execution and delivery of this
Agreement, (a) Buyer and Adelphia have entered into an Asset Purchase Agreement
(the "Buyer Purchase Agreement"), pursuant to which Buyer is to acquire certain
assets of Seller at a closing to be held thereunder (the "Closing") subject to
the terms and conditions set forth therein and (b) Comcast and Adelphia have
entered into an Asset Purchase Agreement (the "Comcast Purchase Agreement"),
pursuant to which Comcast is to acquire certain assets of Seller subject to the
terms and conditions set forth therein.

      3. Termination of the Comcast Purchase Agreement. If the Comcast Purchase
Agreement is terminated prior to the Closing as a result of actions by, or
failure to obtain Governmental Authorizations from, any Government Antitrust
Entity or the FCC (the "Termination"), pursuant to and subject to the terms of
the Buyer Purchase Agreement, the Transaction (as defined in the Buyer Purchase
Agreement) will be expanded as described in Section 5.15 thereof (the "Expanded
Transaction") (the closing of such Expanded Transaction, the "Expanded



Transaction Closing"). Notwithstanding anything to the contrary herein, the
obligations of the parties hereunder shall only become effective in the event of
a Termination. Seller shall give Buyer prompt notice of any such Termination.

      4. Consummation of the Comcast Joint Venture Transactions and Aggregate
Buyer Discharge Amount.

      (a) Notwithstanding the Termination, immediately prior to the Expanded
Transaction Closing, with respect to each Transferred Joint Venture Parent, (i)
Comcast shall cause the applicable Buyer JV Partner to contribute cash to such
Transferred Joint Venture Parent in an amount equal to the Buyer Discharge
Amount for such Transferred Joint Venture Parent, (ii) Seller shall cause such
Transferred Joint Venture Parent to distribute to the applicable Seller JV
Partner (A) cash in the amount of the Buyer Discharge Amount for such
Transferred Joint Venture Parent and (B) all Excluded Assets of the Transferred
Joint Venture Parent and its Subsidiaries and (iii) Seller shall cause the
applicable Seller JV Partner to assume all Liabilities of such Transferred Joint
Venture Parent and its Subsidiaries (other than any such Liabilities that
constitute Assumed Liabilities) (the "Seller Assumption").

      (b) For purposes of this Agreement and the Buyer Purchase Agreement, the
term "Buyer Discharge Amount" means, with respect to each Transferred Joint
Venture Parent, the applicable Buyer Joint Venture Percentage multiplied by the
total amount of Liabilities of such Transferred Joint Venture Parent and its
Subsidiaries as of the Expanded Transaction Closing (excluding any such
Liabilities that are Assumed Liabilities) as determined pursuant to Section
4(d).

      (c) For purposes of this Agreement and the Buyer Purchase Agreement, the
term "Aggregate Buyer Discharge Amount" shall mean the sum of the Buyer
Discharge Amounts for the three Transferred Joint Venture Parents.

      (d) For purposes of making the determination of the Buyer Discharge
Amount, the following procedures shall apply:

            (i) No later than 30 Business Days prior to the Expanded Transaction
Closing, Seller shall prepare, or cause to be prepared, and deliver to Buyer and
Comcast a statement (the "Discharge Statement") setting forth Seller's good
faith estimate of each Buyer Discharge Amount as of the expected Expanded
Transaction Closing (the "Seller's Estimate"). The Discharge Statement shall be
accompanied by a certification of Seller's Chief Financial Officer to the effect
that such Discharge Statement has been prepared in good faith based on the books
and records of the Transferred Joint Venture Parent or any of its Subsidiaries
and shall be reasonably satisfactory to Buyer and Comcast.

            (ii) If Buyer or Comcast in good faith dispute Seller's Estimate
(each, a "Disputing Party"), such Disputing Party shall, on or before the tenth
day



following receipt of the Discharge Statement, so inform each of the other
parties hereto in writing, setting forth a specific description of the basis
parties hereto in writing, setting forth a specific description of the basis of
determination, and the adjustments to the Discharge Statement and the
corresponding adjustments to Seller's Estimate that such Disputing Party
believes should be made (each, an "Objection").

            (iii) If no Objection is received by Seller on or before the tenth
day following receipt of the Discharge Statement, then the Seller's estimates
contained in the Discharge Statement of each Buyer Discharge Amount shall be
final and binding on the parties.

            (iv) If (A) an Objection is received by Seller on or before the
tenth day following receipt of the Discharge Statement and (B) Seller, Buyer and
Comcast are unable to resolve their disagreement regarding any Buyer Discharge
Amounts within the tenth day following receipt of the Discharge Statement, then
Seller, Buyer and Comcast shall refer any remaining disagreements to the CPA
Firm which, acting as expert and not as arbitrator, shall determine, based on
the books and records of each Transferred Joint Venture Parent or any of its
Subsidiaries, and only with respect to the remaining differences so submitted
(and within the range of dispute between the Discharge Statement and any
Objection with respect to each such difference), whether and to what extent, if
any, Seller's Estimate requires adjustment. Buyer, Seller and Comcast shall
instruct the CPA Firm to deliver its written determination to the parties no
later than the five days prior to the expected date of the Expanded Transaction
Closing. The CPA Firm's determination shall be conclusive and binding upon
Buyer, Seller, Comcast and their respective Affiliates. The fees and
disbursements of the CPA Firm shall be borne equally by Seller, Buyer and
Comcast. Seller shall make readily available to the CPA Firm all relevant books
and records and any work papers (including those of the parties' respective
accountants, to the extent permitted by such accountants) relating to the
determination of any Buyer Discharge Amount and the Aggregate Buyer Discharge
Amount and all other items reasonably requested by the CPA Firm in connection
therewith.

            (v) Notwithstanding anything to the contrary contained herein, the
parties agree (and, if applicable, shall instruct the CPA Firm) that the Buyer
Discharge Amount in respect of (1) Century, shall not be less than $297 million
or more than $325 million, (z) Parnassos, shall not be less than $252 million or
more than $275 million and (3) Western, shall, subject to the last sentence of
Section 5.22 of the Comcast Purchase Agreement, be $0.00.

      (e) Notwithstanding the Termination and the Expanded Transaction Closing,
the Plan (as defined in the Buyer Purchase Agreement) shall comply with
subsection (E) of the fourth sentence of section 5.11(a) of the Comcast Purchase
Agreement to the extent applicable to the Buyer JV Partners and the Joint
Venture Securities.



      (f) Nothing herein shall be deemed to limit, release, discharge or
otherwise diminish the Buyer JV Partners' rights in respect of Retained Claims
as against Seller Releasing Parties (other than the Transferred Joint Venture
Parents or any of their respective Subsidiaries).

      5. Release from Retained Claims.

      (a) Effective upon the Expanded Transaction Closing, Comcast, for itself
and its Subsidiaries, and to the extent of Comcast's authority to do so, for its
privies, Affiliates, predecessors, successors, assigns, employees, agents,
attorneys, legal representatives, heirs, executors and administrators, and their
respective shareholders, members, managers, officers and directors in their
capacities as such (the "Comcast Releasing Parties"), hereby releases, acquits
and forever discharges the Transferred Joint Venture Parent and its Subsidiaries
and Buyer and Buyer's Affiliates, predecessors and successors, as well as
Buyer's direct and indirect privies, advisors, consultants, assigns, employees,
agents, attorneys, legal representatives, shareholders, members, managers,
officers and directors in their capacities as such (other than Seller and its
Affiliates except for the Transferred Joint Venture Parent and its Subsidiaries)
(the "Buyer Released Parties") of and from any Loss arising out of, related to
or derived from (i) any claims, demands, damages, actions, causes of action,
rights, costs, losses, expenses, compensation or suits in equity, of whatsoever
kind or nature (including Retained Claims), against any Buyer Released Parties
with respect to any action or omission by any Transferred Joint Venture Parent
or any of its Subsidiaries prior to the Expanded Transaction Closing and (ii)
any Pre-Closing Management Liabilities (as defined below), in each case whenever
accruing, whether foreseen or unforeseen, whether known or unknown, whether or
not well founded in fact or in law, whether in law or in equity or otherwise,
whether direct, consequential, compensatory, exemplary, liquidated or
unliquidated, which such Comcast Releasing Party, or which its legal
representatives, successors, assigns, heirs, executors or administrators ever
had, now has, can, shall or may have for or by reason of any matter, cause or
anything whatsoever, for all periods.

      (b) Effective upon the Expanded Transaction Closing, Seller, for itself
and its Subsidiaries, and to the extent of Seller's authority to do so, for its
privies, Affiliates, predecessors, successors, assigns, employees, agents,
attorneys, legal representatives, heirs, executors and administrators, and their
respective shareholders, members, managers, officers and directors in their
capacities as such (the "Seller Releasing Parties"), hereby releases, acquits
and forever discharges the Buyer Released Parties of and from any Loss arising
out of, related to or derived from (i) any claims, demands, damages, actions,
causes of action, rights, costs, losses, expenses, compensation or suits in
equity, of whatsoever kind or nature (including in respect of Retained Claims),
against any Buyer Released Parties with respect to any action or omission by any
Transferred Joint Venture Parent or any of its Subsidiaries prior to the
Expanded Transaction Closing or (ii) any Pre-Closing-Management Liabilities, in
each case whenever accruing, whether foreseen or unforeseen, whether known or
unknown, whether or not well



founded in fact or in law, whether in law or in equity or otherwise, whether
direct, consequential, compensatory, exemplary, liquidated or unliquidated,
which such Seller Releasing Party, or which its legal representatives,
successors, assigns, heirs, executors or administrators ever had, now has, can,
shall or may have for or by reason of any matter, cause or anything whatsoever,
for all periods.

      (c) Notwithstanding the foregoing, the parties expressly understand and
agree that the waivers and releases granted in clauses (a) and (b) of this
paragraph 5 are made solely for the purpose of inducing Buyer to consummate the
Expanded Transaction by providing evidence of the effectiveness of the Seller
Assumption as provided under paragraph 4(a) above and shall not (and shall not
be deemed in any way to) limit, diminish or otherwise adversely affect any
Liabilities (i) of the Seller or its Affiliates (other than the Transferred
Joint Venture Parent and its Subsidiaries) to Comcast or its Affiliates, or (ii)
of the Transferred Joint Venture Parent and its Subsidiaries payable to Comcast
or its Affiliates under the Plan with respect to Claims asserted in their
capacity as creditors (unless and to the extent the Seller Assumption is
effected in accordance with this Agreement and such amounts are payable by
Seller and its Affiliates under the Plan).

      6. Assignment of Management Contracts. Effective upon the Expanded
Transaction Closing, Seller shall, and shall cause each of its Affiliates to,
convey, transfer, assign and deliver to Buyer all right, title and interest
under (a) the Management Agreement, dated December 7, 1999, between Century-TCI
California, L.P., and Chelsea Communications, LLC, (b) the Management Agreement,
dated January 8, 1998, between Western NY Cablevision, L.P. (f/k/a Parnassos,
L.P.), and Adelphia Cablevision, LLC (f/k/a Adelphia Cablevision, Inc.), a
limited liability company, and (c) the Management Agreement, dated December 30,
1998, between Parnassos, L.P., and Adelphia Cablevision, LLC (f/k/a Adelphia
Cablevision, Inc.), (the agreements referred to in clauses (a), (b) and (c),
collectively, the "Management Contracts"); provided, however, that Seller and
its Affiliates shall retain, and there shall be excluded from the sale,
conveyance, assignment or transfer to or assumption by Buyer under the Buyer
Purchase Agreement any Liabilities arising under or related to the Management
Contracts and attributable to, arising under or related to actions, omissions,
circumstances or conditions occurring prior to the Expanded Transaction Closing
(the "Pre-Closing Management Liabilities"); it being understood that all
Pre-Closing Management Liabilities shall be Excluded Liabilities for all
purposes, pursuant to the Buyer Purchase Agreement. Seller hereby represents and
warrants to Buyer that on or prior to the date hereof it has delivered or made
available to Buyer true and complete copies of the Management Contracts. Seller
hereby covenants and agrees that from and after the date hereof it will not
amend, supplement or otherwise modify a Management Contract in any manner that
is adverse to the Buyer Indemnified Parties.

      7. Cooperation and Consent of Comcast; Books and Records. Comcast shall,
and shall cause each of its Affiliates (including each Buyer JV



Partner) to, cooperate and following the Termination to use good faith efforts
to fulfill as promptly as practicable the conditions precedent (other than the
Termination itself) to the respective obligations of Buyer and Seller under
Section 5.15 of the Buyer Purchase Agreement. Comcast hereby expressly consents
to the Expanded Transaction. From and after the Expanded Transaction Closing,
Buyer shall not, and shall not permit its Affiliates to, provide Comcast or any
of its Affiliates any Excluded Books and Records that Adelphia identifies to
Buyer (in a manner that is readily apparent to Buyer) as "Excluded Books and
Records" at the Expanded Transaction Closing; provided, however, that Buyer may
provide Comcast with any such Excluded Books and Records if it is required to do
so pursuant to applicable Law. So long as Buyer uses good faith efforts to
comply with the immediately preceding sentence (in a manner that is consistent
with Buyer's policies regarding treatment of its own confidential information),
Buyer and its Affiliates will have no Liability for any Loss suffered as a
result of any disclosure of Excluded Books and Records, whether to any Seller
Releasing Party, Comcast Releasing Party, Transferred Joint Venture Party (or
any of their respective Subsidiaries). Comcast acknowledges on behalf of its and
its Affiliates that the foregoing sentence shall be deemed to modify and amend
any requirement in any of the JV Documents to provide Books or Records to
Comcast or any of its Affiliates. Comcast shall not take any action that would
cause the condition set forth in Section 6.2(j) of the Comcast Purchase
Agreement not to be satisfied, provided, that nothing herein shall limit,
release, discharge or otherwise diminish the Buyer JV Partners' rights in
respect of Retained Claims.

      8. Termination. This Agreement shall terminate automatically upon the
earlier to occur of (a) the termination of the Comcast Purchase Agreement in
accordance with its terms for any reason other than a Termination; (b) the
termination of the Buyer Purchase Agreement in accordance with its terms and (c)
the Closing. If this Agreement is terminated pursuant to this Section 8, this
Agreement shall become void and of no effect without liability of any party
hereto (or any Affiliate, shareholder, director, officer, employee, agent,
consultant or representative of such party) to the other parties hereto, except
that no such termination shall relieve any party hereto of any Liability
resulting from any willful breach by such party of this Agreement.

      9. Fees and Expenses. All costs and expenses incurred in connection with
this Agreement and the transactions contemplated hereby shall be paid by the
party incurring such expenses except as otherwise provided for herein.

      10. Specific Performance. The parties recognize that their rights under
this Agreement are unique and, accordingly, the parties shall, in addition to
such other remedies as may be available to any of them at law or in equity, have
the right to enforce their rights hereunder by actions for injunctive relief and
specific performance to the extent permitted by applicable law so long as the
party seeking such relief is prepared to consummate the transactions
contemplated hereby. The parties agree that monetary damages would not be
adequate compensation for any loss incurred by reason of a breach of the
provisions of this Agreement and



hereby agree to waive the defense in any action for specific performance that a
remedy at law would be adequate. The parties waive any requirement for security
or the posting of any bond or other surety in connection with any temporary or
permanent award or injunctive, mandatory or other equitable relief.

      11. Counterparts; Effectiveness. This Agreement may be signed in any
number of counterparts (including by facsimile), each of which when executed
shall be an original and all of which taken together shall be deemed to be one
and the same instrument. This Agreement shall become effective when each party
hereto shall have received a counterpart hereof signed by the other party
hereto.

      12. Governing Law; Submission to Jurisdiction; Selection of Forum; Waiver
of Trial by Jury. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO PRINCIPLES
OF CONFLICTS OF LAW. Each party hereto agrees that it shall bring any action or
proceeding in respect of any claim arising out of or related to this Agreement
or the transactions contained in or contemplated by this Agreement exclusively
in the Chosen Courts and solely in connection with claims arising under this
Agreement or the transactions that are the subject of this Agreement (a)
irrevocably submits to the exclusive jurisdiction of the Chosen Courts, (b)
waives any objection to laying venue in any such action or proceeding in the
Chosen Courts, (c) waives any objection that the Chosen Courts are an
inconvenient forum or do not have jurisdiction over any party hereto and (d)
agrees that service of process upon such party in any such action or proceeding
shall be effective if notice is given in accordance with Section 13. Seller
irrevocably designates The Corporation Trust Company as its agent and
attorney-in-fact for the acceptance of service of process and making an
appearance on its behalf in any such claim or proceeding and for the taking of
all such acts as may be necessary or appropriate in order to confer jurisdiction
over it before the Chosen Courts and further stipulates that such consent and
appointment is irrevocable and coupled with an interest. Each party hereto
irrevocably waives any and all rights to trial by jury in any legal proceeding
arising out of or relating to this Agreement or the transactions contemplated
hereby.

      13. Notices. All notices, requests, demands, approvals, consents and other
communications hereunder shall be in writing and shall be deemed to have been
duly given and made if served by personal delivery upon the party for whom it is
intended or delivered by registered or certified mail, return receipt requested,
or if sent by telecopier or email, provided that the telecopy or email is
promptly confirmed by telephone confirmation thereof, to the Person at the
address set forth below, or such other address as may be designated in writing
hereafter, in the same manner, by such Person:



To Buyer:

                           c/o Time Warner Cable Inc.
                           290 Harbor Drive
                           Stamford, CT 06902-6732
                           Telephone: (203) 328-0670
                           Telecopy: (203) 328-3295
                           Email: glenn.britt@twcable.com
                           Attention: Chief Executive Officer

With a copy to:

                           Legal Department
                           Time Warner Cable Inc.
                           290 Harbor Drive
                           Stamford, CT 06902-6732
                           Telephone: (203) 328-0631
                           Telecopy: (203) 328-4094
                           Email: marc.lawrence-
                                  apfelbaum@twcable.com
                           Attention: General Counsel

                           -and-

                           Time Warner Inc.
                           One Time Warner Center
                           New York, NY 10019
                           Telephone: (212) 484-7980
                           Telecopy: (212) 258-3172
                           Email: Paul.Cappuccio@timewarner.com
                           Attention: General Counsel

                           -and-

                           Paul, Weiss, Rifkind, Wharton & Garrison LLP
                           1285 Avenue of the Americas
                           New York, NY 10019-6064
                           Telephone: (212) 373-3000
                           Telecopy: (212) 757-3990
                           Email: kparker@paulweiss.com
                                  rschumer@paulweiss.com
                           Attention: Kelley D. Parker
                                      Robert B. Schumer



To Comcast:

                           Comcast Corporation
                           1500 Market Street
                           Philadelphia, PA 19102
                           Telephone: (215) 665-1700
                           Telecopy: (215) 981-7794
                           Email: ablock@comcast.com
                           Attention: General Counsel

With a copy to:

                           Davis Polk & Wardwell
                           450 Lexington Avenue
                           New York, NY 10017
                           Telephone: (212) 450-4000
                           Telecopy: (212) 450-3800
                           Email: dennis.hersch@dpw.com
                                  william.taylor@dpw.com
                           Attention: Dennis S. Hersch
                                      William L. Taylor

To Seller:

                           Adelphia Communications Corporation
                           5619 DTC Parkway
                           Greenwood Village, CO 80111
                           Telephone: (303) 268-6458
                           Telecopy: (303) 268-6662
                           Email: brad.sonnenberg@adelphia.com
                           Attention: Brad Sonnenberg

With a copy to:

                           Sullivan & Cromwell LLP
                           125 Broad Street
                           New York, NY 10004
                           Telephone: (212) 558-4000
                           Telecopy: (212) 558-3588
                           Email: korrya@sullcrom.com
                           Attention: Alexandra D. Korry


                  [Remainder of page intentionally left blank.]



            Please confirm your agreement with the foregoing by signing and
returning a copy of this Agreement to the undersigned.

                                       Very truly yours,

                                       ADELPHIA COMMUNICATIONS CORPORATION

                                       By: /s/ William Schleyer
                                           -------------------------------------
                                           Name: William Schleyer
                                           Title: Chief Executive Officer and
                                           Chairman

                                       COMCAST CORPORATION

                                       By: /s/ Arthur R. Block
                                           -------------------------------------
                                           Name: Arthur R. Block
                                           Title: Senior Vice President

Expanded Transaction Letter Agreement


Agreed and Acknowledged:

TIME WARNER NY CABLE LLC

By: /s/ David E. O'Hayre
    -----------------------------------
    Name: David E. O'Hayre
    Title: Executive Vice President,
           Investments

Expanded Transaction Letter Agreement