Sentinel Energy Services SC 13G/A .

Sentinel Energy Services (STNL) SC 13G/ASentinel Energy Services Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

Under the Securities Exchange Act of 1934

(Amendment No. 1)*

SENTINEL ENERGY SERVICES INC.

(Name of Issuer)

UNITS, EACH CONSISTING OF ONE CLASS A ORDINARY SHARE, $0.0001 PAR VALUE,

ANDONE-THIRD OF ONE WARRANT

(Title of Class of Securities)

G8062D128

(CUSIP Number)

December 31, 2018

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐

Rule13d-1(b)

☒

Rule13d-1(c)

☐

Rule13d-1(d)

*	The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended (“Act”), or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

CUSIP No. G8062D128


1.	Names of Reporting Persons Brenham Capital Management, L.P.
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a) ☐ (b) ☒
3.	SEC Use Only
4.	Citizenship or Place of Organization Delaware
Number of Shares Beneficially Owned by Each Reporting Person With:		5.	Sole Voting Power 0
		6.	Shared Voting Power 0
		7.	Sole Dispositive Power 0
		8.	Shared Dispositive Power 0
9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
11.	Percent of Class Represented by Amount in Row (9) 0%
12.	Type of Reporting Person (See Instructions) PN, IA

CUSIP No. G8062D128


1.	Names of Reporting Persons Brenham Management, LLC
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a) ☐ (b) ☒
3.	SEC Use Only
4.	Citizenship or Place of Organization Delaware
Number of Shares Beneficially Owned by Each Reporting Person With:		5.	Sole Voting Power 0
		6.	Shared Voting Power 0
		7.	Sole Dispositive Power 0
		8.	Shared Dispositive Power 0
9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
11.	Percent of Class Represented by Amount in Row (9) 0%
12.	Type of Reporting Person (See Instructions) OO

CUSIP No. G8062D128


1.	Names of Reporting Persons Brenham Master Fund, L.P.
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a) ☐ (b) ☒
3.	SEC Use Only
4.	Citizenship or Place of Organization Cayman Islands
Number of Shares Beneficially Owned by Each Reporting Person With:		5.	Sole Voting Power 0
		6.	Shared Voting Power 0
		7.	Sole Dispositive Power 0
		8.	Shared Dispositive Power 0
9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
11.	Percent of Class Represented by Amount in Row (9) 0%
12.	Type of Reporting Person (See Instructions) PN, HC

CUSIP No. G8062D128


1.	Names of Reporting Persons John Labanowski
2.	Check the Appropriate Box if a Member of a Group (See Instructions) (a) ☐ (b) ☒
3.	SEC Use Only
4.	Citizenship or Place of Organization United States
Number of Shares Beneficially Owned by Each Reporting Person With:		5.	Sole Voting Power 0
		6.	Shared Voting Power 0
		7.	Sole Dispositive Power 0
		8.	Shared Dispositive Power 0
9.	Aggregate Amount Beneficially Owned by Each Reporting Person 0
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions) ☐
11.	Percent of Class Represented by Amount in Row (9) 0%
12.	Type of Reporting Person (See Instructions) IN, HC

Item 1.

(a) Name of Issuer

Sentinel Energy Services, Inc.

(b) Address of Issuer’s Principal Executive Offices

1000 Louisiana Street, Suite 3850

Houston, TX 77002

Item 2.

(a) Name of Person Filing

This statement is being jointly filed by and on behalf of each of Brenham Capital Management, L.P., Brenham Management, LLC, Brenham Master Fund, L.P. and John Labanowski. Brenham Capital Management, L.P. serves as investment adviser to and managing general partner of, and may be deemed to beneficially own securities owned by, Brenham Master Fund, L.P. Brenham Management, LLC serves as general partner to, and may be deemed to beneficially own securities owned by, Brenham Capital Management, L.P. Mr. Labanowski is the manager and sole member of, and may be deemed to beneficially own securities owned by, Brenham Management, LLC.

Each reporting person declares that neither the filing of this statement nor anything herein shall be construed as an admission that such person is, for the purposes of Section 13(d) or 13(g) of the Act or any other purpose, the beneficial owner of any securities covered by this statement.

Each reporting person may be deemed to be a member of a group with respect to the issuer or securities of the issuer for the purposes of Section 13(d) or 13(g) of the Act. Each reporting person declares that neither the filing of this statement nor anything herein shall be construed as an admission that such person is, for the purposes of Section 13(d) or 13(g) of the Act or any other purpose, (i) acting (or has agreed or is agreeing to act together with any other person) as a partnership, limited partnership, syndicate, or other group for the purpose of acquiring, holding, or disposing of securities of the issuer or otherwise with respect to the issuer or any securities of the issuer or (ii) a member of any group with respect to the issuer or any securities of the issuer.

(b) Address of Principal Business Office or, if none, Residence

The address of the principal business office of each reporting person is 3963 Maple Avenue, Suite 290, Dallas, Texas 75219.

(c) Citizenship

See Item 4 on the cover page(s) hereto.

(d) Title of Class of Securities

Units, each consisting of one Class A ordinary share, $0.0001 par value, andone-third of one warrant

(e) CUSIP Number

G8062D128

Item 3.

If this statement is filed pursuant to§§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is:

(a)

☐ A broker or dealer registered under Section 15 of the Act (15 U.S.C. 78o);

(b)

☐ A bank as defined in Section 3(a)(6) of the Act (15 U.S.C. 78c);

(c)

☐ An insurance company as defined in Section 3(a)(19) of the Act (15 U.S.C. 78c);

(d)

☐ An investment company registered under Section 8 of the Investment Company Act of 1940 (15 U.S.C.80a-8);

(e)

☐ An investment adviser in accordance with§240.13d-1(b)(1)(ii)(E);

(f)

☐ An employee benefit plan or endowment fund in accordance with §240.13d- 1(b)(1)(ii)(F);

(g)

☐ A parent holding company or control person in accordance with§240.13d-1(b)(1)(ii)(G);

(h)

☐ A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

☐ A church plan that is excluded from the definition of an investment company under Section 3(c)(14) of the Investment Company Act

of 1940 (15 U.S.C.80a-3);

(j)

☐ Anon-U.S. institution in accordance with §240.13d–1(b)(1)(ii)(J);

(k)

☐ A group, in accordance with§240.13d-1(b)(1)(ii)(K).

If filing as anon-U.S. institution in accordance with Rule13d-1(b)(1)(ii)(J), please specify the type of institution: .

Item 4.

Ownership.

(a)

Amount beneficially owned:See Item 9 on the cover page(s) hereto.

(b)

Percent of class:See Item 11 on the cover page(s) hereto.

(c)

Number of shares as to which such person has:

(i)

Sole power to vote or to direct the vote:See Item 5 on the cover page(s) hereto.

(ii)

Shared power to vote or to direct the vote:See Item 6 on the cover page(s) hereto.

(iii)

Sole power to dispose or to direct the disposition of:See Item 7 on the cover page(s) hereto.

(iv)

Shared power to dispose or to direct the disposition of:See Item 8 on the cover page(s) hereto.

Item 5.

Ownership of Five Percent or Less of a Class.

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following ☒.

Item 6.

Ownership of More than Five Percent on Behalf of Another Person.

Not Applicable.

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.

Not Applicable.

Item 8.

Identification and Classification of Members of the Group.

Not Applicable.

Item 9.

Notice of Dissolution of Group.

Not Applicable.

Item 10.

Certifications.

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect other than activities solely in connection with a nomination under §240.14a-11.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.


Date: February 14, 2019	Brenham Capital Management, L.P.

	By:	Brenham Management, LLC, its General Partner

	By:	/s/ John Labanowski
	Name: Title:	John Labanowski Manager


				Brenham Master Fund, L.P.

				By:		Brenham Capital Management, L.P., its Managing General Partner

				By:		Brenham Management, LLC, its General Partner

				By:		/s/ John Labanowski
				Name: Title:		John Labanowski Manager

EXHIBIT INDEX


Exhibit		Description of Exhibit

99.1		Joint Filing Agreement (incorporated by reference to Exhibit 99.1 to the Schedule 13G filed with the Securities and Exchange Commission by the reporting persons on July 28, 2015).

Brenham Management, LLC

/s/ John Labanowski

Name:
Title:

John Labanowski
Manager