Yes, sorry for the acronyms, sometimes I spell them out and sometimes I assume...
Not sure who would have recommended that, I'd go with 3.6 or 3.65, at least till they get balanced.
Yes, when any one cell hits COVP (or CUVP on discharge) the BMS will at least disable charging, if not take the entire battery offline, until it's 'woken up' by the appropriate procedure, which varies depending on BMS and protection engaged.
I can almost read the part number of the JK(?) BMS, but if you could tell us exactly what one you have, maybe someone with the relevant experience could help with settings. Is it active or passive balancing? I don't think there's a passive balancer anywhere that'll balance 1216AH 'cells', and the usual 2A active balancers will take a week to fix a 25% imbalance...
4P on 304AH cells is going to take a lot of charging and a lot of balancing until you know it's right. I'd have built four individual 304AH batteries, at the very least for ease of access and maintenance. That thing's gotta weigh 300 pounds, and the cells aren't even restrained. In fact, it doesn't even look like there are separators between the cells?
Please tell me this isn't a mobile setup...
Please post pictures of the intererconnect wiring and (especially) the fuses.