"Due to severe congestion you are unable to leave this area, try later"

I've seen this a few times since last week, ALWAYS when trying to enter a house, I presumed the message meant what it said ...

... but this morning around 10:30 on Phoenix when the login queue was 41 (I checked by trying to login a second account and it was placed 41 in the queue) I got it repeatedly for 30 seconds and had to give up getting into my FC house.

Cleary there wan't "severe congestion" (a queue of 41 patently isn't 'severe') so what part of the 'change zone' system is broken at present?