MATS Pt 1, Section 1 Chapter 2 Page 7 under Aerodrome Traffic Zones.....
"Booking Out
Pilots who do not file a flight plan, either full or abbreviated, are required to inform the
air traffic service unit at the aerodrome of their departure. This is referred to as
booking out. The air traffic service unit is to record the departure. No further action is
required."
Hope this helps.