I'm not sure I what else I can do to help resolve this issue. As a Rev main it's rare that this doesn't happen to me in a night of fractals or raids. I've been submitting reports each time though.
For other players hitting this issue, I ran two Revs for a while:
Only occurs if you have more than one Build template configured on Rev - i.e. Set one build, leave the other(s) blank and it's fine. (Tested this with 4 builds on my main, and a 1-build Rev for daily fracs over 170 days). It's only when I added a new template to my fractal Rev that it too started having the same issue.
Occurs on Loading In or Out of instances, seems more prevalent after having touched your template/loadout (but is not consistently replicable). Totally sucked when I had this 3 instances in a row!!
By this point I've lost count of the number of times.
So yeah, it sucks because the 4 templates I have are basically pointless, I have to keep all my acct-wide ones as Rev builds to reapply, and even when you save a template on Ren, it doesn't retain the order of your utilities (these are randomly shuffled). I swear it's the worst class for this to happen to because of that, lol.