QF 744 Question

[Jack B]

I was watching a re-run of "Airport" from the pre-Morissey uniform days, and it featured a delay of a Qantas flight to Sydney operated by VH-OJA, 2 class 744. However, the problem onboard the aircraft originiated in the First Class cabin, and there was footage clearly showing the aircraft had a First class sky-bed style cabin with the old business class seats in the rear cabin. Were all the 2 class 744's originally 3 class?