I just dug up some lilies, and there was almost no new root growth. I really doubt that you will harm them at this time of year, as long as you don't let them dry out. Get them back into the ground as soon as possible.

You can dig them up this time of year , make sure the new hole is well watered don't keep them out to long , you may lose some blooms this year but not necessarily if the dirt balls are big enough , don't dispare!

Get them in their new home asap.