If any of your ringers decide that ringing is not for them or they move away, you can simply log into your manage ringers area, select the ringer and mark them as lapsed.
Their name will then disappear from your current list of ringers. Their profile remains on SmART Ringer and they will still be able to log in and view their account at any time. If this ringer ever returns to ringing either at your tower or elsewhere, they can be unlapsed to either you or another teacher by contact ART Admin.