What happens if you download a Netflix movie that is then taken down by Netflix?
As far as I know, you can no longer look at it, there's an error message
Then you can no longer look at it. Then there's something in the videos. (But I don't know exactly what anymore.)
Incidentally, the film can't go if Netflix still has the license. Offline mode is there to look at something when you MAL have no internet and not, for example, for 2 years as long as the license lasts.
For example for vacation, long journeys without Wi-Fi, etc.
I never thought about when they would no longer work, but I would say after about a month.