I repot all my phals soon after purchase - blooming or not. As noted in the previous post - it doesn't usually affect the flowering. That glass container "potted" phal you just purchased (I believe) was put together for cut flower value - to be admired during blooming, without any regard for the long term longevity of the plant. Until you do repot, just be certain you don't leave extra water sitting in that container. Phal roots need air to survive - the fact that the sphag doesn't appear to be pressed in too tightly will help, but that solid glass container is certainly not helping any. Trim off all roots that are soft and squishy - black and/or dark brown. Enjoy your phal - that's a nice one!