How to handle New Hires During Open Enrollment ( BENEFITS)

Fast Formula for Enrollment Period End Date : " I tried replacing the 90 days with 31 Days in the below Fast Formula , Result is Enrollment window for New Hire shows Balance 31 Days Remaining, But for Open Hire Life event, it still Calculating HireDate +90 Days and allowing the employee to enroll only after 90 days instead of 31 days.

DEFAULT FOR ACP_HIRE_DATE IS '4712/12/31' (DATE)

RULE_VALUE = TO_CHAR(ADD_DAYS(ACP_HIRE_DATE,90))

RETURN RULE_VALUE