I apologise that I’m not able to provide any help with this, I’ve added it to our existing database report but otherwise all I can do is wait on development to return in January and continue their investigation. 
There’s an option under network in the settings. Can’t remember what it’s called, low latency mode or something? Try turning that on or off if it’s turned on. See if that helps?
That was what I meant, smaller network packets. I have to use it, even with 800Mbit/s connection.
I remember having låg issues for ages and actually swapped parts from my spare pc’s to see if it was hardware related. Weirdly enough, using my older motherboard and 16GB of ram instead of 32GB made the game run better. No idea why… after a few patches, I swapped the parts back and there was no longer any issues.
During one patch, my really old i7 860 CPU actually ran the game better than my i9 
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