I see that SRS+BA is a fairly common combo, but from my own experience I would rather have those surgeries separately, specially if we are talking of a sub muscular BA.
I had my BA one year ago and it was the most crippling experience I have ever had. My arms were useless for the week I was at the hospital. Now that I have had my SRS 11 days ago, arm strenght is what is helping me get by, as my lower body / bottom can't take a lot of pressure and I use my arms to getup and position myself. Compared to the BA (and a bit FFS), SRS is being a cakewalk.
I would not dare to combine SRS with anything bigger than partial FFS, specially if alone. If you have a strong companion to help you move, I guess it can be done.