I came across this dialogue:
Is it too late to call them? Do you think they'll have gone to bed yet?
Knowing them, they won't have finished their dinner yet. They'll be watching a film.
My question is why are the future perfect and the future continuous used in these sentences?
I couldn't find any reliable information. In the case of the future continuous it might be "future as a matter of course", but I'm not sure and have absolutely no ideas as to the future perfect here.
I'd be grateful for any ideas.