That is because it is SUPPOSED to be that way.
Remember, in Spring Training, everyone on your 40 man roster is considered to be on your MLB team (It is this way in real life). Thus, when you "option" a player down to the minors, it uses an option.
As in the Show, real life MLB teams must get down to an active roster of 25 players. In doing so, they must "option" players to to the minors, using an option year. (keep in mind, these players can be called up, and sent down as many times during that season as needed, and it still uses only ONE option year).
As for playoff rosters, to be eligible, a player MUST be on the 25 man active roster ON AUG. 31st, or on the MLB disabled list on or before August 31st, to be eligible for the post season.
Thus, "september callups" aren't eligible for the post season roster.
The only exception, is you are allowed to replace an injured player, with any player who was on the 40 man roster as of August 31st.


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