I had a VA related backpay question. Little backstory, I was medically discharged because of a hip injury in 2018, was kind of ushered out and given 80% on my way. I hadn’t realized at the time because at that point I thought it was normal how I was sleeping, but I have some kind of sleeping disorder where I can’t breathe well through my nose and I wake up a minimum of 6 times a night, often more. Idc about the diagnosis, but say I go in to take this test (scheduled in a few weeks), and they find something that raises my claim to 90% or 100%. Would I get backpay from when I got out to make up the difference since I’ve been suffering this whole time, or would it just change the amount I get the following month and so on? Thank you.

Edit: also I’ve never done a claim out of the military, any tips on timing and such would be helpful too!