Full Fibre with Draytek 2862

[#1]

I have recently moved from ADSL to full fibre and am using my own router, a Draytek 2862, with its ADSL WAN disabled and its Ethernet WAN2 enabled as PPPoE with a static IP address.  I connect to my router via VPN regularly from remote sites.  I am having trouble with the link dropping and staying dropped after a variable amount of time ranging so far from 1-5 days.  When it drops it remains in this state indefinitely (only once did it revive itself somehow) and I usually have to restart the router to get it working again - obviously that is a problem if I am trying to connect remotely as it entails a site visit to reboot.  Has anyone else experienced this kind of behaviour? Incidentally when the router was connected via ADSL it was utterly reliable, staying up and connected for months on end.

[#2]

What speed is your full fibre?

[#3]

I'd suggest looking at the WAN Syslog to see what, if anything, is happening with the PPPoE re-negotiation when the connection drops https://www.draytek.com/support/knowledge-base/7528

[#4]

Speed is 74M

[#5]

I do have some logs but they are in a DB format from a synology NAS that the Draytek relays its syslog to. As I can't access the NAS at the moment I need to find out how to open them before I can investigate (I am remote from the Draytek and its currently down).  I have one exported html log showing WAN interaction but I think its at the beginning of a successful session and does not extend to the demise of that session so useful for me to learn the sequences but not diagnostic.

[#6]

A random thought, have you set the connection to be 'always on' ?

Broadband username or login name	yourusername@plusdsl.net
Connection type or encapsulation	PPPoE Always On
Password	The password you use to log in to the My Account
No VLAN tag is required

[#7]

It is not a setting I can choose for PPPoE but in the general setup for WAN it is automatically set to always on