Friend went to Oz recruiting wanting to join the Army and fly helicopters. Recruiter told him the RAAF have helicopters, why not join them. He declined on the basis that they may place him onto some other type. We'll guarantee you fly helicopters in the RAAF if that's what you want. So he did, after a combat tour he was posted to the last Sabre course, when they were disposed of went to Mirage.
Other RAAF chaps I know who went to helos off course went to C-130, one of whom flew the first RAAF C-130 to Antarctica and the other the last C-130 out of Saigon.