Normally when you have a player on trial you'll scout the player in the mean time, after about 2 weeks you will have fully scouted the player.
This is also the case in fm22, however, your scouts will forget everything they learn the day he leaves, so you have to check in the last day before he leaves if you want to see how good he is.
This is a gamebreaking bug for small clubs who doesn't have a handful of scouts.
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