Thanks for the replies! Sounds good, and I did book the hotel Seems like they've stopped upgrading Diamonds in advance from the base room to a balcony room - will see what happens on check-in.

I'll be going from the airport to the hotel a bit after 5 in the evening. Would CAT then changing to U4 be my best bet if I'm getting public transport? Don't mind a bit of a walk (especially if it reduces time on sweaty rush hour public transport).

Any recommendations for somewhere to use the amex platinum dining credit that's easy to get to from the hotel? Ideally with Austrian food. Huth Gathwirtschaft looks alright, but other suggestions are welcome!