Unlocked electronic controls are allocated in batches of 20. The first number of the series always start with 1, eg 181-200, 201-220.

Occasionally even experienced organisers incorrectly plan courses and print maps assuming that the batch is in a different sequence, eg 180-199 200-219.

This causes organiser panic on the day of the event when they can't find control 180 to put out. A messy fix on the day is temporary relabelling of another control as 180 and adjusting the SI Timing event file.

Duplicate start or finish controls
If your event will require duplicate start or finish controls, let the SI Timing manager know this in advance so that the time clocks on these controls can be synchronised beforehand. This is important for sprint events and particularly so where there is a mass start. It will be disappointing after a mass start to be the first of a pair sprinting to the line to punch a finish control but to be recorded in second place due to the time clocks in the finish controls having drifted apart. Time synchronising is routinely done for all controls before OST events only.