My regrade was one that worked in the standard time frame.
Unfortunately what I have found is that the supplied fritz!box doesn't appear to be up to the job. I can get around 600ishMbps OK, but anything above that is very erratic.
To test, I connected up a Mikrotik Hex router and noticed a difference immediately.
Thats more like it!
Unfortunately I don't really like the Hex. Its... very complicated to set up and maintain, and it seems to cause some odd issues occasionally. I don't want odd issues when I'm still working from home full time!
I cannot fault the friz!box for reliability. And it's wifi performance is great (for it's spec. you cant pull more than around 500Mbps from its 2x2 80MHz connection, which is expected). I also use the built in DECT base station for VOIP (data only service).
I may contact them and ask them if they are considering supplying something more powerful that I can upgrade to.