As a fellow breastfeeder and pumper, going on 14 months with my munchkin, I think the better question is, "what won't affect your supply?" Everything and anything and nothing at all can affect your supply. Awesome for you for having a large freezer stash, I was never able to create one as my supply has always been just enough to feed my daughter, plus an extra ounce or two here and there. But back to you... :)
With breastfeeding, as with just abou everything in life, n=1. You are your own experiment. While I can appreciate the others opinions that you should proceed with caution and that you shouldnt do it intentionally, there is a little more to it than that. You said you feel great when you IF, well in my book, feeling great means no stress. And stress can be one of the BIGGEST issues with milk production. Mama is happy = more milk! As for the mechanics of IF, from my understanding of it, you don't necessarily HAVE to eat significantly less calories... It's mostly about timing. (at least that's how I used to do it). So as long as you're eating enough highly nutrient dense food when you do eat and your baby is satisfied with your milk, kudos. If you are trying to IF to dramatically decrease calories and drop weight quickly, well that's bad jujus. However, from every book and article I read on BFing, if you nutritionally deprive yourself in any way while you are nursing, your body will take what it needs from YOUR body to ensure the survival of your nursling. So, be wary of that.
Last but not least, milk supply will wax and wane over the course of your nursing relationship. So in all honesty, if you eat too little for a period of time (speaking from my personal experience) your milk supply may very well drop. As a pumper, I'm sure you know to the ounce how much to expect each session so just monitor that carefully. If it dips too low for comfort (whatever your level is), eat more. Period. I was freaked my supply was drying up Because my pumping volume was about 50% of what it had been for almost a week, so I ate a lot of food (all paleo and upped the carbs) for about a week and my supply skyrocketed. (this was after taking fenugreek to try to increase my supply, and that didn't work for me...).
Anywho, that was probably way more than you wanted to know. :) congrats on the baby and keep up the good work!