This is how the recruitment happens- and there is added stress this year with the logistics of moving people between closing bases/ bases slimming down.
People are held in the holding pool- they have to develop a holding pool before they use all the crew that need to rejoin, they need to be prepared.
This year there are going to be fewer initials at most bases- as for rejoining crew it is only February, half way through the winter. Remember many bases are seasonal which means people are going to be asked to rejoin in time for the Summer when there are many more flights