Subject: substitution

I am trying to figure out how the following substitution will work out:

Initially:
player X on position 2,
player Y on position 3,
player Z - bench

I set the following orders:
min 1, red card/no player, player Y on position 2
min 45, always player Z on position 3

Now, in min 15 player X (pos 2) gets redcarded. Player Y moves to position 2 (first conditional order). What will player Z do in min45:
a) substitution is canceled
b) player Z subs for player Y and plays position 2
c) player Z subs for player Y and plays position 3

a)