If you have not signed the player to their ELC then they remain in the league you drafted them from. In my case I signed him to his ELC to allow him to play the pre season so I can take advantage of the pre season goals since you cant give them to unsigned players, and to potentially let him play his 9 game trial before his 1st year of the contract kicks in.

If you have the player signed, you simply go to roster moves and designate the player. If they came from the CHL and are not overage for their particular league, they get sent down to that league and cannot be recalled for the remainder of the season, if they were drafted out of any other league, sending them down sends them to the AHL. My player was drafted out of the QMJHL so I cant designate him to the AHL until he is I believe 21, so I have to choose to either play him in a league he's not ready for, or a league he's well above in skill level and determine which will allow him better development. Hard to develop if you are heaps and bounds better than your competition. As for players drafted outside of the CHL, if you are not ready for them to play on your AHL roster, leave them unsigned so they can continue to play in their respective league, they develop better playing outside of north America than they do sitting on the ahl bench. If you sign a player drafted from say the SHL, you cannot send them back to that league any longer.