US/Israel have complete control of the skies, over 90% of both Irans defence and offensive capability have been taken out, Irans leaders have been taken out, most of the IRGC infrastructure has been taken out and all of this 3 weeks in.
Israel/US could destroy Iran now within an hour, take out the water/electricity and it's game over. Obviously this is not their intention. There will be lots going on in the background regarding a transition govt that we know nothing about.
Boots on the ground?
My guess is less than another 2 weeks before the regime falls, but it is just that, a guess.