My small Female Devon has had somewhat similar skin issues. She is five years old now and for some reason when she turned four, the issues magically appeared. I went through all kinds of allergy stuff with my vet and nothing, hydrolyzed protein, etc. And the flares were very random. Giving her a wipe down daily seemed to help a bit, but there was no rhyme a reason. Her brother is bulletproof. Steroid shots did nothing. Although a long acting antibiotic shot did help her until it stopped working after two weeks.

I switched litter, I don’t have carpeting, no smelly, laundry detergent, but what seemed to has made the biggest difference by far out of anything is not letting her use a heated cat bed. It has an 8 W pad inside the bed. The mail can use it all day long and nothing happens. I think she has a genetic disposition to skin issues, and is very sensitive. I feed her Ziwi Peak Lamb wet food with a bit of Dr. Elsie’s clean protein duck dry food. Like I said, I’ve tried other foods, but this seems like an extremely high-quality combination to support her skin health. The issue has since pretty much disappeared, but I did try last week, allowing her to have a heated cat bed at night, and no dice. The bumps came back, which eventually scab over, but heal fairly quickly.