OPM told agencies to notify employees of the opportunity to make belated enrollment changes, and to also accept changes through January in the FEDVIP and flexible spending account programs, since a decision on one benefit can influence a decision on another. Belated FEHB changes will take effect with the first full pay period of the year, starting January 4 for most employees, belated FEDVIP changes will take effect January 1, and belated FSA changes will be effective January 1, or the day after the change is received, whichever is later.