I suspect they are finding installs are much quicker than anticipated.
Swap out of two boxes at home only took the engineer at most an hour.
My parents had a new V6, new modem and box moved with new wiring needed and it still only took the engineer 1 and a half hours.
I get the impression that VM had allowed more time for the installs and are now finding that in a lot of cases they can get more done a day than originally planned.