I have heard of a technique where you cut the batting in 3rds.
Place one piece of batting in the sandwich in the center of the top and bottom and quilt that. Makes it easier to just have to get fabric top and bottom under the arm.
After quilting that to with an inch of the end of the batting then take it off the machine and butt up the next piece of batting to the batting already quilted and make a sandwich there and quilt that then do the same for the last piece of batting. Adhesive spray would be a big help.
I'm going to try it someday but it sounds doable for my short arm machine.