I got my replacement FP4 today.
Battery was at 0% and it only booted into:
Android Recovery
Fairphone/FP4eea/FP4
11/RKQ1.210503.001/FP3S
Which asked me to do a factory reset, after which it loaded into Android 11, which updated to 13 and then again to 15.
It’s now sitting at FP4.SREL.15.4.4 and USB works as intended, even after reboot.