Some Scheduling Settings are available as options when starting Learn Sessions

Cards that are passed in a learn session, are considered to be learned until a specific expiration date has passed. The higher the deck, the further away the expiration date is set. For example might a card that has been successfully checked for the first time be scheduled to be relearned one day later again, while a card that has been correctly answered three times in a row be considered as learned for about week. As long as a card is considered learned, it won’t appear in learn sessions.

The scheduling settings allow you to set the exact amount of time a card is considered learned after having successfully tested in a learn session (it won't appear in learn sessions during this time). You can choose from a list of predefined schedules or enter your own custom schedule. Usually it is preferable to use a ascending schedule, that is the higher the deck the longer it should take until the card appears again. Note that the card will always be put back into the start deck if you fail to test it during a learn session.