I imagine lowering the blinds is simply to keep the cabin cooler while it gets prepped for the return
Yep, that’s exactly why. Happens frequently in the desert! Very common at Phoenix as well.
I'm sure you're both right - it's just that even in the height of summer when it's regularly upwards of 100f in LAS I've never been asked to do that on either VS or BA before (so maybe cabin crew regularly do it after passengers are off). Ambient temperature this time was only 70f, though of course a parked aircraft on a gate in direct sunlight will heat up beyond ambient fairly quickly without airco (so possibly an APU performance issue or a gate power issue that meant it might struggle to maintain a reasonable temperature during the changeover).
In the summer the heat in LAS can certainly cause issues with aircraft - didn't Norwegian have issues a couple of years back with 787's in LAS being delayed until later in the evening when temperatures cololed (there were pretty high passenger density on those configs I think, which didn't help, other 787's were able to operate)? If memory serves didn't Norwegian cancel summer flights in/out of LAS in 2017 as a result?
Anyway, thanks again for the thoughts on the blinds issue - I wasn't too alarmed but just wondered if it was something new happening regularly that others had come across or just a one-off.
As for people standing up before the seatbelt signs have been switched off - that seems to be becoming the norm now. Utterly pointless of course - no-one’s getting off any quicker!
Absolutely right Gumshoe - the BA flight I took before this, DUB-LHR as start of an ex EU, was really full (so folks at the back would have quite a wait even once the doors were open) but while I stayed seated until folks were actively moving down the aisle 3 rows ahead of me it seemed the rest of the passengers were standing immediately they thought the aircraft might have stopped (though seatbelt light still on) and then trying their level best to drop some quite heavy carry-ons onto each other!