Source: Elines 

Flight Attendants returning from a single injury, illness 
or maternity absence are reminded, as provided in Section 13.A.5. of the JCBA, if you have used more 
than 255 hours of sick leave you are eligible to begin 
the rapid re-accrual process. A Flight Attendant 
seeking rapid re-accrual must contact her/his 
supervisor who will submit the request to Crew Pay for validation and set up in a timely manner following their return to flight duty. 

Note: Flight Attendants can check their sick and occupational bank hours in CCS under the Pay Tab > Pay register. Scroll to the bottom of the Register and click on Sick Pay >

When eligible for rapid re-accrual of sick leave, Flight Attendants will accrue at the rate of seven (7) hours each month until the Flight Attendant reaches the same level of sick leave they had at the onset of the injury, illness or maternity absence. However, to earn the full higher accrual rates, a Flight Attendant must satisfy the paid activity requirements for each of the quarters where she/he is eligible for rapid re-accrual. 

As a clarification, Rapid Re-accrual applies to sick leave bank hours, not occupational hours.

Additional information, including examples of accruals, can be found in the Sick Leave Guide and in our JCBA, Section 13.A.