swanwick
At night the number of individual sectors are reduced so as to allow one controller to work combined sectors as if they were one big sector; because the traffic loading is less at night. ie one controller will work 3 daytime sectors as one large sector at night
As day arrives the traffic levels increase & the sectors have to be split so as to be capable of handling the traffic.ie the 3 sectors are now split & are worked by 3 different ATCOS.
Apparently, the problems arose when trying to switch back to the daytime system . ie systems didn't work as they should do.