Most likely it's in your post. The first line after the toolchange is not being forced out, because it still thinks it's at that location (i.e. it doesn't know the machine has actually moved).
Usually in the toolchange sequence you'll find a line that says something z =9999 of z = c9k (c9k is a variable set previously in the post, that contains the value 9999)
Because it now thinks the z is at 9999, the next move to z.1 if different, so it outputs it.
But you should be able to force the Z output. look in the ptlchg section of your post for a line that says pzout and change it pfzout. This will force the Z output.
Mike Mattera
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