Yes. You can do that. ONLY over the hole. Eggs are porous, and need to breathe. Be sure no other birds can get to it, and remove the plastic by lockdown.I need help. I opened an air sac on an egg I didn’t think was alive and it is. All the membranes are intact. No pip yet. I think it may even be a duck because candling it just doesn’t look fully developed yet. Should I re-cover the air sac with press n seal or something?
Or, you can just leave it. The shell has served its purpose. The membrane will just be more prone to drying out. Be sure you keep an eye on that.