Constant disconnects for months w/T3 and eventual T4 timeouts

A tech came out weeks ago, replaced the outside connector & box as there was rust.  A hour after he left, I started getting disconnects again.  I was supposed to have a tech out yesterday afternoon but I got a text from Xfinity on Thursday that my appointment had been cancelled.  I've had Pingplotter running most of the day pinging google.com and you can see there's been a lot of downtime today.  I have 2 different modems and the drops happen with either of them.  I switched back to my Arris from the Netgear because it gives better logging.   Drops happen if I'm connected to my router or directly to my PC.

Pingplotter over several hours:  https://imgur.com/lh9KHyk

ttps://imgur.com/lh9KHykhttps://imgur.com/lh9KHykRedacted modem logs:  https://imgur.com/a/9yZqLoP

Signal (~1 hour after modem rebooted):  https://imgur.com/eQrZFwz

https://imgur.com/eQrZFwzhttps://imgur.com/eQrZFwz

The last tech tested for a few minutes inside and out, said everything tested fine after he made his changes outside.  And then about an hour after he left it started disconnecting again.  The last time something like this happened there was an issue down the street.  When it's dropped the connection, the Xfinity app only notices that my modem is offline and doesn't seem to find any issue to my home.

I really need this to work as I'm on-call IT support for a hospital and need to provide after hours support for their staff.  Is there any way to get a supervisor to come out?