Thanks for the feedback. United are now happy to sort out accomodation overnight. Turns out not all passengers were processed onto the next flight - same issues - pickup ticket in LAX story so a little aggravated que formed around the United desk.
NZKarit - Flights originally booked on THZ booking reference but when snow closed UK airports, travel agent rebooked and new booking reference for trip started XRL.
I've spoken to TA who said they can't help re rebooking as Air NZ have taken over the ticket and they will sort? She's been notified by United her bags went on the Air NZ flight she was told she wasn't booked onto - is that even possible ??- so the bags will ' meet' her in Auckland on Saturday. She's just been told at United desk she is re-routing to San Fran in 24 hours then onto Auckland...then CChurch.
Thanks again for the feedback.