So far as I know the clerk does not have an obligation to keep councillors informed that they are nearing disqualification through persistent absence. However, the clerk should keep track of such things, as the council will need to declare a vacancy if more than six months go by and there has not been a council resolution to accept reasons for absence. The vacancy arises automatically at the end of six months; a few days must go by and then the council must note the vacancy and the clerk must put the standard procedures into effect. The clerk (and the council) can, if they choose, advise absent members of the risk of disqualification.