The hotel had confirmed my reservation but then changed its opening date. What should I do?

Consider the following: Did they offer an alternative date? Any alternative date must suit you. If they offer an alternative property, is it in an equivalent room category (sea view, bed types, board basis and similar amenities) at no extra cost? If you bought flights that now need changing, will they cover the change costs? Weigh the offer against these points — but if the new opening date doesn't work for you, you are entitled to a full refund in any event, because the hotel or your agency had confirmed your reservation for those exact dates.