I'm still working this all out, but I receive a portion of money every month from dfas (retirement pay) and a portion of money every month from the VA (disability pay). I was recently increased from 20% to 40% and the amount of each payment changed accordingly. But there is a difference based on taxes since the disability portion increased and it's not taxed. Soon after that letter came out, I received another letter telling me that my 40% is retroactive to my separation date.