Ceres Tactical Systematic (TDFF) 10-K 2017 FY Annual report

Exhibit 10.6(a)

June 1, 2017

Willowbridge Associates Inc.

101 Morgan Lane – Suite 180

Plainsboro, N.J. 08536

Attention: Mr. Steve R. Crane

Re: Management Agreement Renewals

Dear Mr. Crane:

We are writing with respect to your management agreements concerning the commodity pools to which reference is made below (the “Management Agreements”). We are extending the term of the Management Agreements through June 30, 2018 and all other provisions of the Management Agreements will remain unchanged.

• Tactical Diversified Futures Fund L.P.

• CMF Willowbridge Master Fund L.P.

• Orion Futures Fund L.P.

• Ceres Tactical Macro L.P.

Please acknowledge receipt of this modification by signing one copy of this letter and returning it to the attention of Mr. Patrick T. Egan at 522 Fifth Avenue – 7^th Floor, New York, NY 10036. If you have any questions, I can be reached at 212-296-6808.

Very truly yours,

CERES MANAGED FUTURES LLC

By: /s/ Patrick T. Egan

Patrick T. Egan

President and Director

WILLOWBRIDGE ASSOCIATES INC.

By:/s/ Steven R. Crane                    

Print Name:Steven R. Crane           

PE/tr