Hi Manager,
Training with a Transfer coach lasts throughout multiple seasons and during that period, the assigned player is not in your squad. In case your player is back from the Player Academy sooner, i.e. the season when/after your hired him, it can happen that you have recruited another type of a coach. As always, if you want to get in touch with our support team for more information via the "?" option in-game - they'll be able to look into it further and confirm.
Best, macmag123