Disabling the syslog server option fixed the reboots for me on the BT firmware

Interesting observation - I am using a syslog server.

I tried turning off the syslog option. That did allow me to upgrade to the BT version of 3.9.5
I then turned on the syslog option and data was being sent to my syslog server ok.
Tried rebooting and the 2862 did a firmware rollback.

The router that failed, of the 4 I tried, is also using syslog.

I wish I'd read this forum. My upgrade to 3.9.5.all also failed to take (reverting back to 3.9.4.1 after too many reboots). I also use syslog.

not sure if I should upgrade or wait now for the next release, had enough issues with the Draytek 2682ac router, since upgrading from 3.9.2.

I have syslog on and writing to my USB pen drive. 3.9.4.1_BT has been reasonably stable for me, some random reboots every few days (annoying if your in the middle of a zoom / teams meeting) and pretty much daily FTTC drops generally early in the morning.

R