Orbi Pro SRR60 router hijacking DNS queries

> Upgraded to firmware 2.6.0.108. [...]

   From?

> All clients (including the Orbi devices) are assigned the pihole
> server for DNS queries. Nothing has changed from a DHCP perspective.

   Really?  I know nothing, but I'd expect the DHCP server in a Netgear
router to offer itself as the DNS server for a DHCP client.

> The Orbi router is intercepting the DNS requests and resubmitting them
> itself on behalf of the client. [...]

   I'd expect that (or something like that).  The router needs to deal
with special names like "orbilogin.com".  But the implementation of that
"feature" might have changed.

> [...] roll back the firmware to the previous version. [...]

   Which was?