So the night champs has been in SCOA 5 times and Scotland once... interesting
Don't think it is SCOA specifically.
The first two (Ash Ranges and Frith Hill) are SN areas in SEOA, not SCOA. Longmoor is a bit more marginal - being on the SEOA/SCOA border.
If these events were organised by SN/SLOW they should probably be regarded as SE; if by BAOC then you could argue for SC.
What is certainly true is that BAOC are very supportive of night orienteering: at least 6 of the areas are MOD land; and often the event is in conjunction with various Army championships making it more viable.
So perhaps the analysis should read SEOA 5-6 times; SCOA 2-3 times; Scotland once...?