The address of the principal business office of each of the Reporting Persons is 16479 N. Dallas Parkway, Ste 110, LB-14, Addison, Texas 75001.

The principal business of: (i) Westerman GP is serving as general partner of Westerman LP, and (ii) Westerman LP is serving as the sole member of Westerman Family Office, LLC, which manages the family investments.

Neither of the Reporting Persons nor, to the Reporting Persons' knowledge, any director or executive officer of the Reporting Persons (collectively the "Governing Persons"), has, during the last five years, been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors).

Neither of the Reporting Persons nor, to the Reporting Persons' knowledge, any Governing Person, has, during the last five years, been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction as a result of which such person was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

Each of the Reporting Persons are entities formed in Texas.

Westerman LP received the Common Units reported in this Schedule 13D as part of the consideration under that certain Stock Purchase Agreement (the "Purchase Agreement"), dated November 29, 2025, among the Issuer, USA Compression Partners, LLC, a wholly owned subsidiary of the Issuer (the "Buyer"), Westerman LP, J-W Energy Company ("J-W Energy") and J-W Power Company, pursuant to which the Buyer agreed to purchase all of the issued and outstanding capital stock of J-W Energy from Westerman LP for an aggregate purchase price of approximately $860.0 million, subject to certain customary adjustments as set forth in the Purchase Agreement (the "Acquisition"), consisting of (i) $430.0 million of cash and (ii) Common Units of the Issuer with a value of approximately $430.0 million. The Acquisition closed on January 12, 2026 (the "Closing"). The reported beneficial ownership in this Schedule 13D reflects Common Units issued to Westerman LP in book entry form at Closing. No rights to acquire additional Common Units within 60 days of the date hereof are held by the Reporting Persons or any Governing Person. Pursuant to the Purchase Agreement, any purchase price adjustments are addressed through Adjustment Common Units (as defined in the Purchase Agreement) already issued and subject to surrender mechanics, and therefore no additional units are deemed beneficially owned within 60 days. Indemnification Reserve Common Units (as defined in the Purchase Agreement) were issued at Closing and are included, notwithstanding contractual release and legend removal milestones. On July 13, 2026, pursuant to the post-closing purchase price adjustment provisions of the Purchase Agreement, Westerman LP surrendered 30,807 Adjustment Common Units (as defined in the Purchase Agreement) to the Issuer for cancellation. No cash consideration was received or paid in connection with the surrender. On August 11, 2026, Westerman LP sold an aggregate of 9,072,258 Common Units in a private sale to two purchasers pursuant to an exemption from registration under Rule 144 of the Securities Act of 1933, as amended, at a price of $23.75 per Common Unit, for aggregate gross proceeds of approximately $215,466,127.50. No agreements, arrangements or understandings were entered into between Westerman LP and the purchasers in connection with the sale other than customary settlement instructions. The sale was effected from Common Units that were no longer subject to the transfer restrictions described in Item 6 of this Schedule 13D.

The Reporting Persons acquired the Common Units reported in this Schedule 13D for investment purposes as part of the consideration payable in connection with the Acquisition described in Item 3. On August 11, 2026, Westerman LP sold an aggregate of 9,072,258 Common Units in a private sale to two purchasers pursuant to Rule 144 of the Securities Act of 1933, as amended, as described in Item 3 of this Amendment. The sale was made for investment management purposes and does not reflect a change in the Reporting Persons' view of the Issuer or its prospects. The Reporting Persons continue to hold the remaining Common Units for investment purposes. The Reporting Persons intend to continue to evaluate the Issuer's business, prospects and financial condition, the market for the Common Units, monetary and stock market conditions and other further developments. Depending upon, among other things, the foregoing factors, the Reporting Persons reserve their right to review the investment in the Issuer on a continuing basis including the right to (i) dispose of all or part of their remaining investment in the Common Units at any time, (ii) acquire additional Common Units by tender offer, in the open market, in private transactions or otherwise, (iii) propose a merger or similar business combination involving the Issuer or its affiliates, or (iv) take any other action with respect to the Issuer. Except as set forth in this Item 4, neither of the Reporting Persons nor, to the Reporting Persons' knowledge, any Governing Person, has any present plans or proposals that relate to or that would result in any of the actions described in paragraphs (a) through (j) of Item 4 of Schedule 13D.

The aggregate percentage of Common Units reported beneficially owned by the Reporting Persons is based upon 144,943,345 Common Units outstanding as of July 31, 2026 according to the Issuer's Quarterly Report on Form 10-Q filed by the Issuer on August 6, 2026 with the U.S. Securities and Exchange Commission. Pursuant to Rule 13d-3 promulgated under the Act, each of the Reporting Persons may be deemed to be the beneficial owner of 9,072,258 Common Units, which constitutes approximately 6.3% of the Issuer's outstanding Common Units. Except as set forth in this Schedule 13D, to the Reporting Persons' knowledge, none of the Governing Persons is the beneficial owner of any Common Units.

By virtue of its position as the general partner of Westerman LP, Westerman GP may be deemed to share voting and dispositive power with respect to the 9,072,258 Common Units held by Westerman LP. Westerman GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

On July 13, 2026, Westerman LP surrendered 30,807 Adjustment Common Units to the Issuer for cancellation pursuant to the post-closing purchase price adjustment provisions of the Purchase Agreement. No consideration was received by Westerman LP in connection with the surrender. On August 11, 2026, Westerman LP sold an aggregate of 9,072,258 Common Units in a private sale to two purchasers pursuant to an exemption from registration under Rule 144 of the Securities Act of 1933, as amended, at a price of $23.75 per Common Unit. The sale was effected in a privately negotiated transaction. Other than as described in this Schedule 13D, neither the Reporting Persons nor any Governing Person has effected any transactions in the Issuer's Common Units during the past 60 days or since the most recent filing of Schedule 13D, whichever is less.

Not applicable.

Not applicable.

Purchase Agreement. Under Section 8.9 and Section 8.10 of the Purchase Agreement, Westerman LP agreed that, without the prior written consent of the Issuer (as applicable), it will not transfer any equity consideration Common Units during the "Restricted Period," subject to enumerated "Permitted Transfers." The Restricted Period ran (i) for 50% of the equity consideration Common Units until six months after Closing (July 12, 2026) and (ii) for the remaining 50% until twelve months after Closing (January 12, 2027). The Restricted Period applicable to the first 50% of the equity consideration Common Units has expired. The Restricted Period applicable to the remaining 50% of the equity consideration Common Units remains in effect through January 12, 2027. In addition, (A) Adjustment Common Units (as defined in the Purchase Agreement and with a value of $20,000,000) cease to be restricted following the final post closing purchase price adjustment and legend removal, and (B) Indemnification Reserve Common Units (as defined in the Purchase Agreement and with a value of $60,000,000) are released from restrictions in tranches at twelve months and fifteen months after Closing, with any remaining reserve Common Units released upon final resolution of claims, in each case together with related legend removal mechanics. These restrictions are in addition to transfer restrictions under securities laws and any legends required by the Issuer's partnership agreement or the Purchase Agreement. On July 13, 2026, 30,807 Adjustment Common Units were surrendered to the Issuer for cancellation pursuant to the post-closing purchase price adjustment provisions of the Purchase Agreement. Registration Rights Agreement. Pursuant to the Registration Rights Agreement entered into on January 12, 2026, the Issuer has granted Westerman LP certain rights to require the Issuer to file and maintain the effectiveness of a registration statement with respect to the resale of the Common Units issued as the Unit Consideration (as defined in the Purchase Agreement), and under certain circumstances, to require the Issuer to initiate underwritten offerings for the Common Units to be issued as the Unit Consideration. Board Observer Rights Agreement. Pursuant to the Board Observer Rights Agreement entered into on January 12, 2026, from the date of the Closing until the first anniversary thereof, Westerman LP is entitled to appoint one non-voting observer to the board of directors of the general partner of the Issuer (the "Board Observer"). In no event shall the Board Observer (i) be deemed to be a member of the board of directors of the Issuer, (ii) have or be deemed to have, or otherwise be subject to, any duties (fiduciary or otherwise) to the Issuer or its common unitholders, or (iii) have the right to vote on, or consent to, any matters presented to the board of directors of the Issuer or propose or offer any motions or resolutions to the board of directors of the Issuer. Westerman LP has designated Avril Westerman as its Board Observer. No contracts, arrangements, understandings or relationships were entered into between Westerman LP and the purchasers in connection with the private sale of 9,072,258 Common Units described in Items 3 and 4 of this Amendment. The foregoing descriptions of the Purchase Agreement, the Registration Rights Agreement and the Board Observer Rights Agreement do not purport to be complete and are qualified in their entirety by reference to such agreements which are attached hereto as Exhibits 2, 3 and 4, respectively, and are incorporated herein by reference. To the best knowledge of the Reporting Persons, except as otherwise described in this Schedule 13D, there are no contracts, arrangements, understandings or relationships (legal or otherwise) between the Reporting Persons and any Governing Person or between the Reporting Persons, any Governing Person and any other person with respect to any securities of the Issuer, including any class of the Issuer's securities used as a reference security, in connection with any of the following: call options, put options, security-based swaps or any other derivative securities, transfer or voting of any of the securities, finder's fees, joint ventures, loan or option arrangements, guarantees of profits, division of profits or loss, or the giving or withholding of proxies.

Exhibit 1 - Joint Filing Agreement of the Reporting Persons (incorporated by reference to Exhibit 1 to Schedule 13D filed on January 14, 2026: https://www.sec.gov/Archives/edgar/data/1522727/000210302726000002/ex_906860.htm) Exhibit 2 - Stock Purchase Agreement (incorporated by reference to Exhibit 2.1 to the Issuer's Current Report on Form 8-K filed on December 1, 2025: https://www.sec.gov/Archives/edgar/data/1522727/000119312525303103/d16081dex21.htm) Exhibit 3 - Form of Registration Rights Agreement (incorporated by reference to Exhibit B of Exhibit 2.1 to the Issuer's Current Report on Form 8-K filed on December 1, 2025: https://www.sec.gov/Archives/edgar/data/1522727/000119312525303103/d16081dex21.htm) Exhibit 4 - Form of Board Observer Rights Agreement (incorporated by reference to Exhibit C of Exhibit 2.1 to the Issuer's Current Report on Form 8-K filed on December 1, 2025: https://www.sec.gov/Archives/edgar/data/1522727/000119312525303103/d16081dex21.htm)