Extremely slow upload speeds. Continuous Drop outs, and high packet loss....HELP

I tried getting some help at the official Comcast Reddit, but there wasn't much so here I am..... Previous Post below. 

Hi all, I'm in need of help with some internet issues. Here's a quick rundown of what's happening....

It's been about 2 1/2 months of internet issues with this company. It started with Comcast bumping up my internet speeds from 600 to 1000. I then decided to update some other things (cable package, ect) so the speed went up again to the highest tier (1.2 down and 200 up) I received the new XB8 and for about two weeks everything was fine. 

At first the upload speeds would reach 30-70, while download would reach 300-500 depending on the device it was tested on (all on wifi). Fast forward to now and upload speeds have been consistently horrible barely capping out at 5, while down speeds can be anywhere from 30-300.  

The drops aren't long and can range from a few seconds to a few minutes, but they can be constant. There's days when the internet drops 5-15 times, other days when it drops only a few times and recently had FIVE whole days where it didn't drop at all. 

Streaming movies can get annoying with constant buffering and online gaming becomes pointless with all the packet loss and lag fluctuations. 

Random info...I live in a 2400 SQ ft house, the XB8 isn't hardwired to any PC or other devices as wifi is my only way to use it. I have no wifi extenders/pods. There's only around 20-25 devices connected. The coax outlet was looked at by myself and techs and was fine.

Here's what I've personally done as well as what Comcast techs/agents have done.

- Have done the usual tightening of cables and modem resets/restarts/ firmware updates

- Have had 2 techs come out and say the power levels and signals were fine

- Have had the amp replaced twice on the side of the house 

- Have been through 4 XB8 routers/modems

- changed the location of the XB8 

- completely switched out all cables/wires that are attached to the XB8 and any splitters

- Had the underground cable to my house switched out (though it took them two weeks to come back and bury it and in that time there was a lot of snowfall) 

- Even re-added the xfi complete package to my bill thinking it may have been throttling/bandwidth issues 

- when requesting a new XB8 (my second one) to test if that was the problem I received the wrong router (got an xb7 instead) but was curious if it was just an XB8 issue, so I hooked that xb7 up and still...you guessed it, had drop outs

I'm out of ideas on what it could be other then a possible node issue, but there's clearly an issue with this service and it's starting to become an expensive one, and I'm footing the bill for it. Any help would be appreciated.