Had diarrhea this morning, tried to squat, quit during warm ups because I knew if I had to tighten my core as much as I needed I would have had stuff running down my leg.....no more eggs in the morning for me :(
Feels gut cuz of dis:
How much weight are you pushing? You consider yourself an intermediate?
I did fine on IA SPBR, but I've gotten better gains from increased frequency of the main lifts. Squatting every 4th session (like you do on SPBR) wasn't enough for me. You could always keep running SPBR and do some lighter squats for reps or front squats after DLs on Deadlift day if thats a concern.
Otherwise, if you like the routine and you made good progress, there's no reason to change it, especially not if you're going into a cut. Generally, its good to cut with the same program that you built with. When you start a new program, there's always some guesswork on what weights you will use and some tweeking to learn new movements and get adjusted to the changes. This can have you use les weight, which in turn in a calorie deficit could cause muscle and strength loss.
I'd just keep doing SPBR if I were you unless you have anything against it. Add another day for some low impact bodybuilding isolation stuff if you want to (say more arms, delts, quads, whatever) if you manage to recover from it and not have the other days suffer as a result. My guess is that you won't be able to do this and that you will actually need to drop the volume on the regular SPBR template, but at least its worth a try.
If you want to change because you keep stalling out, change some lifts and manipulate the rep and sets with the same total volume. Usually does the trick.