I think I will agree with mayres with a bit of reservation about re-potting with blooms. I am no expert on Phals. but just general plant physiology would suggest some impact on the blooms, perhaps, as innocuous as the life-span of the flowers.
I have done it with spikes since I always re-pot the orchids when I bring them home and I have a vague feeling that the flowers had dropped off prematurely.
Other than that no adverse effect can be seen whenever they are re-potted; and I have done it with more than 30.
sandra may be right if one is inclined to be too cautious ( I am sorry for contradicting ,sandra
). If not, you should follow mayres's advice before they begin to spike.
Good luck.