Interesting to see how a new (well, recycled anyway) port handles this. OOL was very busy yesterday and very unusually for me I arrived at the airport around the time boarding was scheduled to commence. Security took ~5 minutes to get through then went to gate 3. The signage was there, and though boarding had not commenced (it took another 5-10 mins to do so), there was a very long line in the general queue, and a much shorter line in the PB queue (maybe 20 - 25 people?). I've no way of telling who in the PB queue was eligible or not, but after they boarded the little kiddies etc. both queues started to board and on we went.
Was unable to tell how it went in SYD because when I got there there were significant delays to the remaining MEL flights including my 2205 (last of the night). I wandered to the J lounge hoping I might get shifted from to the earlier delayed flight, but instead she said I've got you on 465 (which itself was delayed ~90 minutes), which is in final stages of boarding (it said 'Flight Closed' on the boards) so no lounge for me (not that I'm complaining, it was a great result to get on this flight), had to rush off to Gate 17, where the last few pax were boarding. Long time since I've been in row 45 on a 763!