AR 600-8-2 States some of the following:
1–13. Circumstances requiring a transferable flag
The specific actions and investigations listed below require a transferable flag.
a. HQDA directed reassignment of flagged soldier. Remove the flag according to HQDA guidance.
b. Movement of an adverse action into the punishment phase. Remove the flag according to the rules in paragraph
c. Failure to pass the Army Physical Fitness Test (APFT) or failure to take the APFT within the required period. Remove the flag (code E/type report) on the day the soldier passes the APFT or at expiration term of service (ETS)/expiration of service agreement (ESA)/mandatory release date (MRD).
I was unable to find what they define as the required period, but I'm believe its one year. It also goes on to say:
1–15. Processing exceptions
(1) Flags for APFT failure block promotion, reenlistment, and extension only.
(2) A flag is not initiated if the soldier has a limiting physical profile that specifically prohibits taking the APFT.
That should be what you're looking for.