Section 890.1606 - Opportunities to enroll, change enrollment, or reenroll; effective dates(a) Except as otherwise provided in this subpart, a Postal Service employee may enroll or change enrollment, as provided by § 890.301 , in a PSHB plan and may not enroll in a FEHB plan as a Postal Service employee.(b) Except as otherwise provided in this subpart, a Postal Service annuitant may change enrollment or reenroll as provided by § 890.306 , in a PSHB plan and may not enroll or reenroll in a FEHB plan as a Postal Service annuitant.(c) Except as otherwise provided in this subpart, reinstatement of enrollment in accordance with § 890.305 is permitted in a PSHB plan.(d) Initial decisions and reconsiderations of PSHB eligibility or enrollment will be made pursuant to § 890.1607.(e) Under this subpart, an enrollment, change of enrollment, or reenrollment made during Open Season takes effect on January 1 of the next year.(f) Under this subpart, OPM will effectuate the following health benefits actions: to enroll or change enrollment; to elect not to enroll; and to reenroll. The employing office makes determinations of eligibility under 5 U.S.C. chapter 89, pursuant to application of 39 U.S.C. 1005 . 88 FR 20403 , Apr. 6, 2023, as amended at 89 FR 37079 , May 6, 2024; 89 FR 85029 , Oct. 24, 2024 88 FR 20403 , 6/5/2023; 89 FR 37079 , 7/5/2024; 89 FR 85029 , 10/24/2024