Here's some good info regarding the A1C test from Chris Kresser:
Why hemoglobin A1c is not a reliable marker
tldr: A1C can be skewed high if your red blood cells live longer than average.
Have you checked your numbers fasting, before your first meal and 1 hour post- and 2 hours post-prandial? Doing so can give insight to what's happening. If your numbers actually go down after you eat, maybe you should back off on the IF for a while or cut back on exercise somewhat to try to lower cortisol. If your BG goes really low in the post-meal window it could be reactive hypoglycemia. Lots of possibilities that checking with a glucometer could help figure out.