I'm a big fan of installing something once and never changing software/firmware so it continues to operate the same forever. Sadly, with Windows 10 those days are gone, but even before (with Windows 7), I found my CAD behaved differently after a while. Affected by automatic OS updates, I think.
I've read here of people having to reset an Epever to get it back to producing what it should. But I haven't read that updates were available which fixed anything.
At a time when your battery is low enough to accept the current and not reach full charge for a while, you could try connecting first a single panel directly to it, then each individually, then move up to all in parallel. Looks like battery voltage would be just slightly below Vmp, so should give pretty good charging. Of course, you would need a way to measure the current (if presently relying on SCC for that.)