This has been DC's modus operandi since day 1 of the New 52, and it's distracting and annoying. Justice League International and Justice League Dark both had substantial and wholly unnecessary cast shake-ups after their very first arcs, and Justice League of America became Justice League United and jettisoned a whole bunch of characters I was interested in. I am sure there were other books that I am not remembering that did the very same thing. It seems long gone are the days when teams were actually teams for many months, they grew and gelled together as a unit. Team books have always had cast members leave and new members introduced, but DC seems to think that the wholesale dismantling of a team to add characters that are their current flavor of the month is a good idea.