(1) A guarantee accepted in accordance with these rules is subject to the following terms and conditions:

(a) It shall be in writing, and if necessary shall be renewed in a similar manner annually.

(b) It shall state the terms of guarantee, the maximum amount guaranteed (such maximum not to exceed an estimated one year bill, such estimation to be made at the time the service is established) , and that the utility shall not hold the guarantor liable for sums in excess thereof unless agreed to in a separate written instrument.

(c) Credit shall be established for the customer and the guarantor shall be released upon the satisfactory payment by the customer of all proper charges for utility service for a period of 12 successive months. For purposes of this subsection, payment is satisfactory if:

(i) The utility has not initiated disconnection proceedings against the customer.

(ii) No more than two notices of delinquency have been made to the customer by the utility.

(2) The utility may withhold the release of the guarantor pending the resolution of a disputed discontinuance.