I think going to TR for Xander is a good idea. Make sure to update your signature and spreadsheet to TR to reflect the change. And great job working on the feeding change, that can be so hard!
Feeding before shot times is something we discourage for new people. Once you have enough data (for most people that's a +1 if they feed at PS) and get an idea how much of a numbers bump your cat gets from food, you can feed later in the schedule. You just want to make sure that if their PS is influenced by recent consumption of food, that the PS number is still safe to shoot. Ideally feeding before nadir is still best, as feeding after nadir can shorten duration of the insulin, and give you higher preshots.
Besides lower numbers than they are used to, steep drops can also cause bounces. Last night's 164 PS to 88 at +2 could have been a steep drop, depending at what point he did the drop. And lastly, the AMPS numbers are typically the last to come down, possibly due to dawn phenomenon.