Social Security

My husband is a CSRS retiree. He did not have enough of his own quarters for SS and wouldn’t receive anything from spousal benefits due to the GPO limits so never applied. With the SS fairness act, he applied in January for spousal benefits, and they started him in Dec. 24 so he received a payment in January, with a reimbursement for the Medicare he was paying directly. Should he be receiving a lump sum for 2024? They were not sure in January when we went to the field office for the application, and do we need to follow thru with SS?