Hi HodgesanDY, well so far I haven't actually had to reset/reboot as the link has come back up itself after a while varying from 6 hours to 3 days. It is currently down and no there is no-one who can reboot it for me but once it springs back into life I intend to set a scheduled reboot once a day in the hope that it is at least a workaround. To be honest I am fumbling in the dark with the settings so I assumed PPPoE was the right thing and as it worked first time I assume it WAS right, and the internet up/down indication could be ping rather than PPP but I have not tried that. What does your Virgin line need for authentication is it just done on MAC? BTW previously this router was very stable and reliable when on DSL.

There are no special authentication requirements for the Virgin setup at this 2862’s location. Just put their modem/router in “Modem Mode” and set the Vigor WAN2 settings to Ethernet and Obtain settings automatically.

Detection mode is set to “Always On”

Maybe that's my problem then, the ONT is the equivalent of the Virgin modem so perhaps I don't need the PPPoE setting, I will try some variations once I can either get back in remotely or make a visit. Thanks

I made the trip to reset my router a few days ago and tried setting it to Static or Dynamic IP with always on etc.  It would not allow me access to the internet at all and after an hour or 2 of fiddling I decided to go back to PPPoE and it worked again like magic - until today that is.  So I definitely appear to need to be on PPPoE.
I think it stayed connected for about 3 days in total but I will now have to make another 60 mile roundtrip.  I read something on the Plusnet site about setting VLAN active, with 802.1q ID = 101 and 802.1p ID = 0.  I am not sure where to find those in connection with the WAN2 side?  Always-On isn't available when WAN2 is set to PPPoE and I am not sure whether ARP detect or PING detect is the best one.  With PING detect for WAN down I would have to set a ping target but what to use?  Any IP address I put in (eg Google) might be changed by DHCP and putting in a host name (google.com) isnt allowed.
On my next trip to reboot/reconnect the router I will be attaching a D-Link 4G modem in an attempt to gain remote access even when the fibre I/F has gone down so that (I hope) I don't have to keep making the trips.
Another option that occurred to me is to use the Plusnet router in bridge mode - I don't know much about that - will my draytek still be able to dhcp through the plusnet to get its WAN IP address or will the plusnet give the draytek a local IP address?  I have a ddns set up that the draytek knows about and getting a local address would break that.  Any help gratefully received, thanks!

@steveM84

You definitely need PPPoE for Plusnet. For FTTP the Openreach ONT removes the need for VLAN tags.

Follow this (using yourusername@plusdsl.net where it says bthomehub@btbroadband.com and your Plusnet password)

https://www.draytek.co.uk/support/guides/kb-fttp-wan-setup

If it's unreliable I might try a different PSU (buy a "real" Draytek one).

Also, you don't need to bridge the Plusnet Hub 2 with FTTP, that won't help.

To detect the connection is up "PPP Detect" is what you want.