Repot in bloom?

[butterfly_muse]

I know, I know, you're not supposed to repot an orchid while it is in bloom. I just acquired this beautiful phal, but upon inspecting her when I got home, I pulled her out of her cup and a bunch of her roots are mushy, black and brown. There are also white and green spots and white fuzz around a lot of the dead roots (which I suspect is fungus). Additionally, she seems over-crammed into her cup...as in the roots are causing the cup to be oblong instead of round because they are bulging inside of it. I was not able to get a look at the roots before I bought the orchid because there was plastic wrapped around the rim of the pot.

I have attached pictures. I am afraid to repot it, but I am even more afraid to leave it like it is. Any tips?