T3 and T4 errors causing internet connectivity problems for a week now

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Greetings. I work from home and rely on a stable internet connection to address technical issues for universities in and outside of the U.S. This last week my xfinity internet has been going down every 5-10 minutes, also presenting an issue for the users I support. My modem logs show many T3 and T4 timeout errors. Xfinity dispatched someone to our home yesterday and they replaced the coax and connectors that run to our home. We didn't have any issues for an hour and then the T3 and T4 errors started raging again. The tech that came to our home told me that if the issue persists, it is likely a problem with my modem or inside wiring. I've replaced the ethernet cable from the modem to the router, I've ensured no kinks are present in the coax that runs to the modem and that it is securely fastened, I've powercycled my modem, router, and computers, I have reset the modem and router to factory defaults, and I've re-provisioned the router. After reading countless xfinity customer experiences regarding the same issue, in most cases the issue originates from the provider's equipment/wiring. I know it's a holiday weekend and we will probably not see anyone address this now, but it would be nice if xfinity could have someone look into their equipment and wiring as soon as possible. Here's a screenshot of my modem logs:

The upstream power is on the high side and it may be intermittently fluctuating even higher to out of spec levels. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels. The below tips may or may not apply but I'll include them anyway;

In an effort to try to obtain better connectivity / more wiggle room, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1000 MHz, bi-directional, and no gold colored garbage from Radio Shack, Home Depot, Target, etc. Splitters should be swapped with known to be good / new ones to test.

Also check the coax cable for any damage such as cuts, nicks, kinks, sharp bends, etc.

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two-way splitter connected directly off of the drop from the street / pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to get the techs involved again until it gets fixed properly.

Bear in mind that if the premises facing techs can not find or fix a problem at your home, it is they who are responsible for escalating it to their line / network / maintenance dept. techs. The problem may lie beyond your home in the local neighborhood infrastructure somewhere but it is their S.O.P. to start at the home. And if the problem is found to be on their side of the demarcation point, there will not be any charge.

Good luck !