Substitution
The provision as it is printed, and everything on Ruleside that turns on it.
If there is a fourth official, the AR does not need to move to the halfway line as the fourth official carries out the substitution procedure unless there are several substitutions at the same time, in which case the AR moves to the halfway line to assist the fourth official.
Verdicts that turn on it 1
Walk the tree to any of these and this clause is part of the answer.
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