I'm on SSDI for bipolar. I was approved in 11 weeks which is really fast but happens occasionally. I got a check about a month after approval I think; I don't remember that very well. Reviews are done either every 3 years (typical) or 5 (rare with mental health). I was very fortunate to have family help while waiting for approval. I don't know what would have happened if it took longer. I did have a long time without insurance but was able to use charity care to see my pdoc and get the medical care I needed.