I didnt run pihole -r as i didnt want to lose settings etc.
I did, however manually change /etc/pihole/setupVars.conf to show the correct ipv6 address seen via ifconfig and it seems to have fixed partly fixed the issue.
I now have internet access via VPN.
So im gonna go out on a limb and say my local IPV6 address for my pihole changed...?...
still multiple queries to api.github.com just looking at this FAQ thread Use IPv6 ULA addresses for Pi-hole
i see that in my ISP router settings under LAN TCP/IPv6 Setup, there is an option "Enable ULA Router Prefix Advertisements" which is turned on.
So i guess the code that @DL6ER hints at isnt required?
Is there any way to determine if IPV6 address changes, or of the ULA changes?
Please excuse me if theres are silly questions, im very much still learning, and do appreciate your time in helping me.