From what i can make out the methods of complete setting for a confirmed system are only to be from a protective switch, shunt lock, pts button or door contact. but then nsi say this:
NOTE 1 This prohibits the use of a timed exit procedure whereby, following initiation of the setting procedure, the IAS sets after a given time has elapsed. This is because of the possibility of a false alarm if the time is accidentally exceeded.
Part setting:
Clause 6.3 of the BS covers completion of the full setting procedure (to fully set the IAS). Therefore there is a certain amount of flexibility in terms of part setting the IAS. However, methods used to part set IAS should minimize false alarms. Always check with the local police force to see if they accept confirmed intruder alarms when the IAS is part set.
So its kind of contradictory, but looks as though it shouldn't be a confirmed from a part set unless checked?