Actually I was feeding every 3-4 days, probably too often but I have so many rats and mice I'm getting over run LOL. I actually changed things up again, I reduced the hotspot temps back down to 88F (from 90F) and removed the Repitchip from the back of the tubs like it was before, I'm going back to the old setup. The other thing I realized is that not only did the temps over the hotspot change but the actual hide itself changed. When you move the Reptichip away from the hotspot it makes a sort of hide within the tub, so they sit in a deep depression with a ridge of Reptichip around them. Perhaps that gives them extra security. So maybe it was a combination of temps and security. I decided to go back to the original setup since almost none of my ball pythons have eaten for the last four feedings!
Also, my retic didn't eat his big ol rat on the last feeding. I'm thinking she reached a size to where her metabolism has slowed down, I was feeding her twice a week as well. Sometimes I would give her a big rat and sometimes she was getting one or two smaller rats left over from other non-eaters. This is the very first time she has never taken a rat. She went through some explosive growth though, I'm thinking I can cut her back to once a week or so. She is nice an hefty and has some nice girth on her. She used to eat a big rat and two days later she was super skinny again, not anymore!
I've also decided to feed once every five days instead of every 3-4 days. I have a wide range of ages from hatchlings all the way to adults, this is sort of a happy medium. I'd like to offer my youngers at least once every five days, if the adults miss a meal then they go to every 10 days.
It could be the time of year as well. As far as my ambient temps I actually increased my room temp from 75F to 78F in the last month or so, seems like the tubs dry out faster when the temps are hotter.
Also, I think some snakes were getting red spots from poor maintenance. I've decided to remove each snake from the back of the tubs, spray down the back with Chlorhexidine and wipe it dry at least twice a week to keep things a bit cleaner. I also clean the same way if I notice a real dirty tub or if I can smell my retic LOL.