Just returned from a 4 night stay 13-17 May - used a Hyatt Visa suite night, one BWB night and 2 nights on points.
Pool open. Great Club lounge. We had a nice suite on the 6th floor on the SE corner. Not much of a view, but a nice room.
Treated very well as a Diamond. The lounge had a nice continental breakfast and great happy hour. Hotel is an easy walk to Taksim Square (easy to take funicular to light rail to go to Sultanhemet).
Only criticism is that it is a conference hotel and the rooms did not have balconies.