MrNitch,
Short answer; yes.
So, for each huntgroup, A-C, you will need to create another huntgroup to Recall to that has a higher priority than A-C, but a lower priority than Z. This new huntgroup can reuse the same extension list(s) as Z with no problem.
Hunt Group A [priority 0] recalls to Hunt Group D [priority 10].
Hunt Group B [priority 0] recalls to Hunt Group E [priority 10].
Hunt Group C [priority 0] recalls to Hunt Group F [priority 10].
Hunt Group Z [priority 50].
So, when a call comes into Hunt Group Z it will have a higher priority than Huntgroups D-F and therefore its calls will be offered first to an agent that has just become available to take another call. There will be times when an agent will be offered a call from one of the Huntgroups D-F if those calls have already queued up on the agent before the call comes into Huntgroup Z; if that makes sense. So, basically if the agents becomes available to take a call and there aren't any calls in Huntgroup Z and they are offered a call from one of the other Huntgroups then they are no longer considered available for when a new call comes into Huntgroup Z, but the next available agent will get the Huntgroup Z caller before receiving a Huntgroup D-F caller.
Thanks,
TE