Dropped packets after recent network upgrades

One week ago we had 'service done in our area' and ever since this service was completed we have had dropped packets happening every ~5-15 minutes for 5-10 seconds resulting in complete disruption to work and personal calls as well as general inconveniences across general Internet use.

The issue happens on all devices, across all applications, across wifi and hard wired, and on both 5GHz and 6GHz. I have spent 5+ hrs with customer service over chat and two technicians have come out to my house. The first technician ensured that the coax was directly routed to the modem and replaced the modem with a brand new one. The second technician did some basic testing at various locations in the system. Both technician's tests were passing (although the second had an initial failure reading at the line into the house which he brushed off). Given the infrequent nature of the issue, the online support test also show the 'signal is strong' given that 95% the signal is fine but the instability makes the internet worthless for the work that my wife and I do. 

I am looking for any advice on how to actually get through to someone at Xfinity who can profile my internet for more than 5 minutes and help actually come up with a solution to my issue. We have had zero issues in the past until the 'service was done in my area' one week ago.