How soon is repotting needed here

[Roberta]

Cyms like to be potbound - they bloom best just as they are breaking the pot. I would wait until spring - after the bloom, to repot. It won't be harmed by having the new growths be a bit crowded for a few months. Cyms are NOT fragile. For now, just let it bloom.

A hint when you are trying to get a potbound Cym out of the pot... squeeze the pot (or step on it to compress it a bit) or give the pot a few good whomps on the side with a wooden mallet. That will tend to release roots that are stuck to the pot. Then if you still can't get it out, cut the pot. Pots are cheap, roots are precious.