What I love about all the tech calls I get, is there is no issue anyone here can have that I have not had a call on, these calls are the greatest tool SPI has to know what is going on with a product and I have heard it all.
One thing I have never had a call on is the issues you just asked about.
Something I did back in 99 or 2000 that you might find interesting.
The 55 Chevy was blasted body and frame at the same time, I epoxied the frame outside and the body inside the garage, the front end I took off in one piece and next day when epoxy was dry I carried the whole front end up to my wifes garage and it sat there for over 90 days while I did the body work and the frame.
The front end only had about four ping dings and a 6 inch area that needed filler, so I applied the glazing putty and the filler to the epoxy without sanding first, sanded and then shot 2K primer over the whole front end without sanding.
Saw the car Saturday while neighbor was pulling whole shots in his driveway for his kids, not a chip or issue of any kind. Great test and real world testing.
I should add, I'm not recommending this and the reason I did it was for own curiosity and I can take the font end off the car in about an hour, if I needed to redo it.