CAX80 (AX6000): multi-gig ethernet port and botched firmware update

OK, so it's possible that the info I'm working from here is incorrect, in which case, please politely correct me, but unless I'm wrong, the most recent firmware update for the CAX80 somehow screwed up the multi-gig ethernet port (i.e. the MOST important ethernet port on the modem/router).  The port was working fine until we updated to 2.1.1.4, at which point I keep getting inconsisten connections and full-blown disconnects.  I read that that was a result of a problem with that firmware (again, please correct me if I'm wrong).

But assuming this is correct, I'm wondering if there is a timeline for when this will be fixed.  I'm not even sure how much control we have over that firmware since it's pushed to us by comcast, so I'm not sure it's possible for us to revert to a previous version, and the problems with that port are kind of driving me nuts.  The obvious workaround is to plug my ethernet into one of the other ports, which I'm doing for now, but that means slower and less consistent speeds/latency, and it kind of defeats the purpose of having a $450 router in the first place - that was one of the cool selling points of this router in the first place.

Any help would be appreciated.