Custom DNS - possible to conditionally use custom DNS entries?

[ojwc]

Hi all, with simple mapping in custom DNS such as the example in the docs:

customDNS:
  customTTL: 1h
  mapping:
    printer.lan: 192.168.178.3
    otherdevice.lan: 192.168.178.15,2001:0db8:85a3:08d3:1319:8a2e:0370:7344

Is it possible the configure Blocky to use custom DNS for certain clients or client groups, and for others send the request upstream? I use simple mapping to redirect requests for my domain to the server's private IP address when those requests come from my main/trusted VLAN, but for devices on the server VLAN this causes problems (eg Caddy fails to get https certificates unless its DNS requests are sent upstream). I use two Blocky instances to get around this, one is the upstream server for the other and doesn't have the custom DNS config.