Mine took about an hour when I turned it on one morning this week. I have no idea when it downloaded (I shut off the laptop every night). IE STILL does not work - hasn’t since the 8.1 upgrade, but now Edge won’t work either. Outside of that, no problems with the update.
I had to use Cortana to find IE, it wouldn’t even show up on the start menu, and it was taken off my task bar. But I have it back now.