If (condition 1) is true
and the occurrence of (condition 1) is the first since the last occurrence of (condition 2)
then do x
This would also mean that if condition 1 is met on a subsequent occasion then it would be ignored unless there is a new occurrence of condition 2.
I hope that is clear.
I have looked at MRO, LRO and Countlf() but can't figure out if any of these are suitable.
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