Unfortunately, if you are approved for Federal Disability Retirement, you do not qualify for the Special Retirement Supplement.
The special retirement supplement represents the amount of Social Security you earned while working in your FERS position. In order to be eligible for this additional benefit, you must retire on an immediate, unreduced annuity before reaching age 62. Therefore, if you take a deferred annuity or are approved for Federal Disability Retirement, you will not receive this additional payment.