UPDATE: Apologies for not following up until now. I ended up using a sheet metal style wall patch. I used tin snips to cut my 4” hole. Then I patched into the ceiling like a normal wall patch. Some mudding tape, couple coats of mud and some patient sanding later, it looks mint. Time will tell if any cracking occurs. Thanks for all the suggestions.
I’m installing 4” LED Halo recessed lights. It’s a plaster ceiling and the hole I cut quickly chipped away to much larger than the required 4” diameter. I don’t want to repair with a drywall patch because of the condition of the ceiling (I’m nervous the plaster will crumble out of control). Is there a way to patch this so that I can still retain the 4” hole for the light, but repair the edges of the hole so the diameter isn’t more than 4 inches?