yes I do.

I’ve run out of configuration suggestions and it seems to be that the link between the Openreach ONT and the Draytek fails for unknown reasons.

I wish I was convinced that replacing the Draytek would fix this but I’m not.

Putting Plusnet’s Hub 2 in the chain (as previously suggested) in bridge mode is an obvious next step.

It could easily be the ONT.

Yes I am of a similar mind. I did wonder about the ONT, I seem to be able to twist it on the wall as if it isn't screwed down tight, but that may be normal. I will try the Hub2 bridged when I am able to spend some time there (its a simple job but I know it will take upwards of an hour as simple jobs do) and I am also thinking the same as you about replacing the Draytek - especially with another Draytek. It's currently down, has been for over 24hrs now, but one last thing I might try is switching back to full hardware acceleration without the LAN traffic graph once I regain connection. It did stay up for 10 days before I turned on traffic graph to see what LAN things were connected (albeit with a few short lived drops). If that works, I would put it down to lack of processing speed. If the Hub2-bridge works then its looking more like a new router.

Hi Guys, its been a long time since I gave any update on this so here is what's been happening since I last posted.  I made a site visit (went home) and put the Plusnet router back online.  This meant I could access certain things such as the central heating and not much else.  The router behaved impeccably with no drops and a typical response graph being all green
(https://www.thinkbroadband.com/broadband/monitoring/quality/share/c6b5509d374f852c84b7136128d7faa11a78fcb5-06-11-2024). During a later site visit I tried the Draytek 2862 again but it would not recognise the ONT on its Ethernet WAN port so I suspect that port is faulty and that has been the source of my problems. It may just need resoldering but...
I also ordered a new Draytek 2927 and made yet another site visit to install it. With that in place there have been no drops; I can connect to the hive heating and I can VPN into my home network as normal. I am having a little difficulty in getting some of the wifi clients to connect to the new router for some reason - this is an ongoing investigation - but the situation is very much better now. One thing I noticed though is that the Draytek 2927 does not respond so quickly to the pings on thinkbroadband monitor
(https://www.thinkbroadband.com/broadband/monitoring/quality/share/232bc3a036b8b5f4fe8176e28a97ffb7fedba1c0-15-12-2024)
giving a lot more yellow than the Plusnet hub did. I don't seem to suffer from any slow operation when I VPN or remote login so I guess that's just the firewall doing its stuff maybe.So the final result for me is that I think it's fixed to my satisfaction and I want to thank everyone who has contributed to this thread.

That's a very yellow Thinkbroadband monitor.

My guess would be significant upload traffic at all times.

Yellow spikes with a slope on one side seem to be a "Draytek thing".

A previous router had lots of those until a firmware upgrade which seemed to (mostly) sort it.

There shouldn't be much traffic at all in either direction most of the time. Only real traffic should be when I vpn in. I ran a ping from an rPi and the times were typically 20-30ms but with the odd one up to 250 - 500ms. Not brilliant but not too bad I think.