If you have a leader who is no longer serving in a position in your unit you can click on their name from the leader roster page and then enter an end date on their position.
NOTE: this will not remove the leader from the BSA membership.
For example if have a committee member who moved away and is no longer in your troop just enter an end date into his committee member position.
Once a leader no longer has a position in your unit they will automatically fall off your leader roster.
Do not delete the position because this will affect the tenure of the leader. It is also nice to have a history in Scoutbook of who served in your unit.
It is important that you never delete a leader’s account either. The leader may be tracking their own Scout, he or she may be serving as a merit badge counselor for the district or the leader may return to Scoutbook later and serve again in another unit.