Now I might be a bit simplistic in my thinking here, so if someone can please put me straight...
If an A330 diverts into AVV due to missing the Sydney curfew, then presumably the a/c will have to position up to Sydney asap the next day to do its next scheduled run... so would it not make sense, rather than take an A320 (or two) off the domestic loop (so causing the knock-ons) and running a now-empty A330 back up to Sydney, to simply fly the diverted A330 - with pax - to Sydney to arrive when the curfew lifts at sparrow's the next morning?
Or would the absence of night-shift ground handlers at AVV have delayed the repositioning of the A330 until later in the day?
I'm sure that if the following had been put to a vote, the punters would've voted to stay on: "OK people, we've missed the Sydney curfew, so we can either all stay on the aircraft until first thing, take off and get to Sydney at 05.30am, or we can wait on the aircraft until we've found you all hotels (which may take until, say, 3am), bus you all to the hotels at 4am, let you sleep, bus you back at, say, 10am, fly you up to Sydney to get you there in time for lunch". (Note that I am not actually suggesting such things be put to a vote but as intelligent people I'm sure you understand what I'm saying here.)
It just strikes me that, on those rare but regular (two or three days per year) when Sydney gets fogged in, other carriers manage to get back on-track reasonably smoothly... what's different with the 'star?