It totally depends on the airline and is different from one airline to another. There is no standard way of distributing schedules. Some of the ways that I have personally experienced or have seen it:
Bids by seniority: The crew will bid for flights/rosters based on their seniority. Juniors will cry rivers.
Fair share: The crew will get turns, if you take ...
It depends where you are flying, i.e. which countries rules apply. In the US for example, the minimum cabin crew is determined by the seating capacity:
For airplanes having a seating capacity of more than 100 passengers—two flight attendants plus one additional flight attendant for each unit (or part of a unit) of 50 passenger seats above a seating ...
I can only speak for carriers following FAA regulations. But, It was probably a company policy change. I have a copy of the 2017 FAR/AIM. I don’t remember there being a change since then.
One reason for an air carrier, whether large or small, to use a standard format and phrases is to make sure that every flight and cabin crew completes all of the required ...
"Flight attendants stand by for all call" commands the cabin crew to be ready at their station to report to the chief purser via intercom.
See the explanation on this and other airline phraseology on