Representatives of a group of 3,500 Central Maine Power ratepayers sent a letter to the utility company’s President and CEO Doug Herling detailing a series of problems with bills and service and asking that a thorough investigation be conducted. The letter follows a request by Maine Public Advocate Barry Hobbins to the Maine Public Utilities Commission to upgrade its summary investigation, which is delving into the technical aspects of CMP’s billing and smart meter system, to a comprehensive adjudicated investigation. Hobbins’ request was denied by the PUC, which said it was premature as the summary investigation was still underway.