Hey guys it was quite last minute over here too - but then these guys are traveling around the world doing this assessment and they are all pilots/cabin crew (at least the ones in the UK were) aswell so I guess it's just a case of sit, wait and see, they'll respond when they can.
If you have been given a date and city - why not aim to get there the evening before anyway so you can be relaxed and rested.
Though I personally couldn't afford to stay in NYC anywhere nice............