Form and Presentation. A supplier and the utility shall provide written notice of enrollment to a customer entering into a service agreement with the supplier on the next business day following the supplier's receipt of the utility's enrollment response. If a customer's billing method changes, the notice of enrollment shall contain a statement that the customer's previous billing providers may still bill the customer for unpaid charges. A supplier's presentation of a signed copy of the customer's contract at any time before enrollment constitutes sufficient written notice of enrollment to the customers. Enrollment Notice Content. An electricity supplier shall provide notice of enrollment of a customer to a utility in a format consistent with the Commission-accepted utility supplier coordination agreement. Notice of enrollment under §B(1) of this regulation shall include the following: Customer account name; Customer service address; Billing name; Billing address; Utility name; Utility account number; Supplier name; Supplier account number; Commodity provided; Effective date of the enrollment; and Whether the customer will receive supplier-consolidated billing service.