Final answer:
ACDU and FTS E-9 personnel receiving an HYT waiver typically forfeit eligibility for future promotions and selective continuation, impacting retirement benefits and reenlistment options.
Step-by-step explanation:
Active Duty (ACDU) and Full Time Support (FTS) enlisted personnel at the E-9 level who are receiving a High Year Tenure (HYT) waiver may be required to forfeit eligibility for certain benefits. In the context of the U.S. Navy, a HYT waiver allows a service member to continue serving past the time they would ordinarily be required to retire due to reaching the maximum years of service allowed for their rank. When an E-9 service member receives an HYT waiver, they may have to give up their eligibility for future promotions and selective continuation, which can also affect their retirement pay calculations and eligibility for future reenlistment.