I applied for SSDI last year by mail. My claim expires 7/23. In March of this year is when I received the claim that nèeds to be filled out by a doctor. I've tried getting my primary doctor and Rheumatologist to fill out the form, but no one is willing to do it. My guess is I may have to pay out of pocket. My question is, if I submit the claim form after the 23rd. Will I be paid retroactively?