I did another test with this image, where in V5, before upgrading
- removed all the adlists (58) except the original Steven Black default one at the top of the list
- removed all domains (99), a mix of exact and regex white and blacklist entries
- removed all clients (2) which had been present in an unrestricted group
- removed the unrestricted group, leaving just the Default group
- updated Gravity
- rebooted
Then did the upgrade. No change in previously reported results.
I was testing upgrading from the same OS, etc but a simplified setup more akin to how Pi-hole V5 was after a new install, in case quantities of lists or some obscure regex rules were being parsed in some edge case way.
Another test, disabling the DHCP server and deleting the leases in V5 before upgrading, followed by a reboot.
Then did the upgrade. No change in previously reported results.
I was testing if the DHCP server being enabled or disabled made any difference to it being disabled after the upgrade. Made no difference, became disabled either way.