Anyone who was eligible to access the Sydney or Melbourne businesses lounge can now access the First lounge. This includes Qantas Club members traveling on a QF or JQ flight number plus one guest traveling on the same flight. In Sydney or Melbourne the Qantas Club Annual Guest Card would also be accepted.
In New Zealand (AKL, WLG, CHC and ZQN) the Air New Zealand lounges are treated as Associated lounges (just like the pre covid CHC and ZQN lounges). Therefore anyone with a Qantas club card can access the Air NZ lounges prior to a QF flight number (and perhaps JQ someone might be able to confirm?) with one guest traveling on the same flight. Guest cards and single-use invitations wouldn't be accepted at these lounges.