In the late 1990s, QF started making patterns that had a 29 hour slip in JNB and AIPA took the matter to the Industrial Relations Commission. They were successful with the grievance due to safety/fatigue - and that was for PER-JNB-PER operations. The longer SYD-JNB-SYD ops definitely need 48 hours due to the length of the flight and the 9 hour time zone change - the biggest change in a single sector in QF ops.