Traditionally, there was an early finish on Thursday at most offices (I believe in order to preparte for the holy day), but these days most organisations (including Government Offices) are moving to a 5 day week with Thursday being a normal working day and Friday/Saturday off.
The early finish Thursday is a disaster in any business (including Aviation) which has dealings in Europe or US because.
Thursday you finish just as they are starting (Europe) or well ahead of their start (US)
Friday your day off
Saturday go to work and Europe/US are off
Sunday go to work and Europe/US are off
Monday half the day is gone before Europe turns up and three quarters before the Cousins arrive at their desks.
Voila - a 5 day AOG !!!