Flew JFK-LHR departing 2130 recently in PE and haven't flown from JFK in about a year and I was intrigued this time there was no bar service offered. It was just the meal service offered with wine or water. Then in the morning, we were only offered water, tea or coffee.
You can ask for another drink (for example apple juice). at any time but it was never offered or avaliable on the cart with the meals or other.