The answer to your question will vary based off what kind of winters you have. Where in NC do you live?
Here in sunny south Cackalacky I have had some great success repotting deciduous trees in early Fall/ late summer. Depending on how early in the season you do it, you might consider at least a partial defoliation to lessen the strain on the roots after they get worked... I did a late summer repot on a JM I have last year (inspired by a FB post from Walter Paul where he repotted a huge JM Bonsai he has) The concern is that a early freeze might damage newly developing roots. We had one of our coldest winters ever here last year and the Map,e was SUPER happy this Spring!!
CM is a little more cold sensitivity an maples in my experience, so I would encourage you to provide protection over winter during the coldest nights- whether you re pot it in Fall or not.
The benefits are many- you are usually stimulating an end of season growth spurt for your tree (both the roots and the branches) by pruning and getting it into a new pot with more room... My Maple last year shot out a 2 foot shoot between late September and when it started to go dormant (just a couple months). This is good for developing trees obviously not a great asset for more developed/ established trees, but the increased ramification tends to naturally limit the growth... The real benefit for me- again, dealing with trees Iw ant to fatten up and continue to develop- is that you start the next growing season with a tree that has already established itself in the pot! No chopping roots and eliminating all that stored energy from dormancy, no waiting for the tree to bounce back through half the Spring when it should be growing... As soon as the leaves are ready to pop, the tree is going full speed! It is like gaining an extra growing season almost.
The timing is important, but it is best to error on the side of doing it early if you have harsh winters to contend with. WE all think trees are best repotted in the Spring, but the trees don't know that... They respond to good care, and it doesn't really matter when you do it, it is the after care and soil medium you use that is more important than timing. You can repot in mid-winter if you protect the tree, or mid- summer if you give it some shade until it starts growing... The idea that it is best to repot in the early a Spring is- I think- primarily meant to mean that is the easiest time for most people to do it because the temps are moderate, the trees are about to start growing again which quickly reassures us we repotted at the right time... In other words it is a blanket recommendation meant to make it easy especially for beginners. It is not a hard rule based off of biological necessity.