Ruling A = If a player enters the Field of Play and prevents the scoring of a Try, a Penalty Try 
will be awarded and the offending player sent to the Sin Bin.
Ruling B = If a player enters the Field of Play but does not impede the scoring of a Try the 
offending player will be sent to the Sin Bin.
17.8 Following a Try, players may Interchange at will, without having to wait for the 