The integration agreement protects both Q and A pilots. That is Qantas (Q) and Australian (A) airlines pilots in both airlines prior to the merger of 92'.It basically determines who will fly what for Qantas Airways Ltd whilst a Q or A pilot is employed by Qantas.
I believe that the provisions of the integration award that are relevant to this discussion were incorporated into the SH award in the last EA. So now, even if the integration award were to expire (as it's relevance with regard to seniority of A and Q pilots diminishes as the years pass), the relevant points regarding fleet and flying protections are incorporated into the Contract and can't just be disregarded.