Think there's still work being done/they're still playing with the signal so I think I need to give it a day or 3 for the signal to stabilise, literally 12 inches difference in router location is meaning the difference between 11 ping, or 22 ping, and 220mbps download, or 600mbps download...
I might also have a cable issue somewhere as when I was seeing 600-700mbps on wifi direct to the router, I was only seeing 300mbps on ethernet, via a couple of switches. I've a feeling where the router is currently is right on the edge of the 2 mast signals and it's connecting to one or the other with tiny movements in location.
And don't get me started on the 5G stats, the fastest speeds seemed to coincide with the worst signal!!
On the plus side, I timed a 1GB file download to take under 13 seconds. That's quite frankly ridiculous.