Bobby,
The way it worked for me was, I collected disability insurance from my company, then SS took effect after six months. The disability insurance company helped me file. It was to their advantage, because they did not have to pay as much when I went on SS. It was 9 months after my diagnosis that I filed. SS paid me back money to the 6 months, but not for the first 6 months, I had to pay the disability company the back pay I got.