Speaking for myself, I would not say something like "I have secured accommodations on a flight to Cairo next Tuesday." Those are "reservations" or simply "a seat."
I've got a reservation on a flight to Cairo on Tuesday.
But yes, we do use it in the plural to mean "a play to stay."
In BrE, until very recently, we used accommodation only as a non-count noun; however, recently I have begun to see/hear such things as "We have booked accommodations for all the new trainees".
There are 42 British National Corpus citations for accommodations, 4,300 for accommodation.