Considering that the Chinese Elm is sub-tropical and that you have already re-potted it you could bring it inside if you have a good location for it. They don't need the same length of dormancy temperate trees do.
Trees that have buds swelling can still be left, a few cold nights and they seem to slow down again. I sometimes get a few buds that break early while the majority stay tight longer. Even buds that break and remain small are not really a problem. If the trees in question can stay in their current pots another year that might be an option. Evaluate each tree individually, if you must re-pot one this early it should receive extra protection.
I would not be too anxious to encourage your trees to break dormancy this early. Are these trees in a shed or garage? Are they getting a lot of sun during the day? You might want to reevaluate your storage strategy for next year. It is best to keep them dormant as long as possible so a location that does not warm up too early is preferable.
I find that there are a few weeks each spring that I must be ready to move things back and forth but it is way too early to be doing that. My advice is to wait it out if at all possible.