Sounds like your have some sweet compost!

And I can't help you other than smart comments lol

SCG

I was going to say, most likely not honey bees in compost but when you say composter, ...if it's some sort of encloser/barrel/box etc. then yes, honey bees like them to set up new colony.

Turning compost now would kill them,...let them be for winter, most likely, it'll kill them too without any protection in our harsh winter.
If you want to try to save them,.. put sheets of fiberglass insulation into black trash bag and tie with strings around, do it now. The entrance,..probably too large, you can cut a reducer, Styrofoam/plug, drill a hole not bigger then a dime.
No guarantee,..if bees moved in later in the season they don't have enough food store build up to make the winter, you can feed them now, mix white sugar, 2 to 1 with boiling water water then put into a container, [put about 8 foot or so beside the hive] put a bunch of wood stick on top so bees don't drown. A Queen is with them all the time, she might still have some brood going/new bees, these new bees are also important for winter survival. Come spring and they made it then they can be re-located by a beekeeper.
Picture would help.

It is one of the black barrel shape composters It has more composters on either side as well and chain link fence at the back. There are 4x4 grills all the way around for air flow. I will leave them alone for the winter and see what happens come spring. I don't need to empty it now I can always shove the 100 sq ft of watermelon plant into garbage bags for the winter thanks