The PPA basic plan document language in Section 4.02(b)(1) provided an optional true-up if the match allocated based on the determination period would have been more had the match calculation been completed on a Plan Year basis. With the Post PPA (Cycle 3) document, this language was removed at the request of the IRS. However, that does not mean that an optional true-up is not permitted, just available in more limited circumstances.
For details on when an optional true-up is permitted for both traditional matching contributions and safe harbor contributions, you can refer to our Post PPA Matching Contributions Q&A document.