A 4 man crew can go to 16 hours and then extend to 20 maximum if they agree to it. At no stage was anyone being forced to go beyond 20 hours, so nothing untoward here. The aircraft returned to LAX and departed for AKL straight away with a fresh crew.
My mail is that it was the 2nd major LAX disruption in 2 days as the cabin crew got off the aircraft in NY due to a diversion and delay on the way inbound.
As for 3 man operations from BKK up to LHR and return, this is normal for this time of year and has been going on for longer than I have been on the 400. Keep to the facts people, chinese whispers won't do anyone any good.