Happened multiple times in the past month — getting put into a LFR group where the remaining bosses are only the ones you’ve already killed.
I seem to recall if you got put into an in progress group, after completing it, you will always be put into fresh group so you can complete the remaining bosses you haven’t finished.
Putting players into groups where the only bosses available to them are the ones they’ve already killed for the week really shows no respect for player’s time because players get absolutely nothing out of it — it’s a complete waste of time — and also can’t leave without getting deserter rebuff.