Quite a few, but Community Managers can't give an answer when there is no good answer. All they can do is rely what devs tell them - and if devs have nothing to tell, go figure.
I've been through 4 moves in 3 different UK companies, and they barely take 10 minutes of your time as employee.
On last day at last place (usually friday) you get crate at your desk - you put your things into it. Next week you come to new workplace and your stuff is already here, your IT kit is set up and you ready to go (with only minor hiccups sometimes).
Saying that "office move" prevents normal functioning of a company for weeks, would be *highly* unusual.
I've worked for companies where the Christmas do seating plan caused months of drama the likes of which even god has never seen, you never really know till you see from the inside.