I remember some discussion on this but don't remember exactly what we ruled.
1. If you sign a minor league players before he reaches his 50/150 status, can you release him?? wavier wire him??
2. If a minor league contract is expiring and you do not want to release him, you can sign him to a major league contract?? This player must remain on your active roster until he reaches 50/150 status (ala Desmond Jennings a few years ago).
1)if you sign a player b4 50/150 that means you got him from the MiLB draft. now during the year you can promote/demote him as many times as you want. but because he is considered a minor leaguer you cant cut him until just b4 the MiLB draft(drop up to 4 players) once he reaches 50/150 you can launch him. no waiver for him b4 50/150 2) you can sign him and play him but if he doesnt get to 50/150 b4 his minor contract is up then he is lost to minor league fa and you are liable for his contract. the situation happened to me this year. i traded for fujikawa(chubs), gave him 1 year and promoted him(600K-1). well he went down to tj surgery and his minor contract has expired and i have to pay his salary for 5 seasons. no on the active roster since in our game he can have a major league salary but still considered a minor guy. he would be a minor guy with salary.
I found a discussion on this. It was based on the Desmond Jennings trade a few years ago with Pittsburgh. I don't think this thread went anywhere but my point is I'd rather sign a minor league player with expired years (zero), who I think will be an impact player in the future than lose him to the MiLB draft thus keeping my initial investment. Maybe I should have brought this up last year before I lost Shelby Miller. We all will be in this situation in the future, so what we decide will be equally fair for everyone.
This is where I stated if you choose to sign a player in this situation, as a drawback he must stay on your active roster until he reaches 50/150 status or contract expires. Kind of like a rule 5 draft in MLB.
Selby Miller was lost under the original minor league rules. New rules have been added a couple of years ago to allow players drafted by that team, to have the possibillity to be signed to the major league roster up to 5 yrs and 600k, even though they may not have the 150/50 minimums, but they will take up a major league roster spot.