., a player is added to the 40-man roster,the team has three different seasons to send him to the minor leagues without having to clear waivers. A player on the 40-man roster playing in the minors is on optional assignment. FYI when a player is sent down you will notice it reads he was optioned to S/WB. There is no limit on the number of times a club may promote and demote a player during one option season.
A player must spend at least 20 days total in the minor leagues during one season (not including rehabilitation assignments) in order to be charged with an option. He can go up & down aka the S/WB shuttle numerous times in a season but only one option is charged..
Cessa has used the three options and must now clear waivers to be sent down - the Yankees do not feel he would so they are keeping him. Also, a player who with at least five years of major league service time may not be optioned to the minors without his consent.