Can confirm that if you reboot the router, tailscale starts looping up and down again (shows yellow in the main GIU) and the only thing you can do to get it up and running again is to stop the network interface using LuCI which allows it to settle down and connect. Very fustrating.
I have also tried manually updating the tailscale version (as described here: Script: Update Tailscale on (nearly) all devices ) but the same behaviour persists - so its not the version of Tailscale that is at fault here.
Hoping a person smarter than me can help you! A script is a good idea - but long-term Gli.net need to fix.
I’m on v4.8.3 at the moment but the patch notes for the next version don’t mention this issue or tailscale at all ( GL.iNet download center ).