PORTLAND, Maine — Utilities regulators have decided to investigate FairPoint’s landline service quality performance from 2015, despite insistence from the company that a 131-day strike and winter weather were unavoidable challenges.

The move puts the company’s performance for six consecutive quarters under the microscope, in an investigation in which regulators will determine whether to assess penalties against FairPoint for not hitting benchmarks.

In an order issued Tuesday, the Maine Public Utilities Commission lumped together its investigation of FairPoint’s performance from mid-2014 through the end of 2015, finding the company’s results were “generally similar for each of the quarters, and its explanatory letters contain generally similar reasoning.”

The company has argued that some of the requirements established by the commission are unreasonable, including a requirement that it meet more than 99 percent of its installation appointments.

The order, issued Tuesday by Commissioners Mark Vannoy, Carlisle McLean and Bruce Williamson, didn’t buy that argument.

“The Commission does not agree with FairPoint that the benchmarks for the service quality standards that the Company failed to meet are unreasonable or unattainable,” the order states, adding that FairPoint’s relatively large customer base compared to other landline providers “does not necessarily provide a rationale for FairPoint’s repeated and consistent failure to meet the [service quality] benchmarks.”

Lawmakers on the joint Energy, Utilities and Technology Committee on Monday advanced a bill that would lighten those service quality requirements in conjunction with a larger bill that gradually frees FairPoint from an obligation to provide price-capped landline service in areas where customers have sufficient choices between FairPoint and other telephone and Internet providers.

That bill would adjust some of the metrics FairPoint missed by the widest margin, such as the percentage of network troubles not resolved within 24 hours. Using a moving annual average, the company had more than 60 percent of network troubles not cleared in that timeframe.

By the current quality requirements, regulators reported the company in 2015 exceeded the allowable rate of troubles per 100 lines, the percentage of installation appointments not met and the average delay (in days) of appointments.

Darren is a Portland-based reporter for the Bangor Daily News writing about the Maine economy and business. He's interested in putting economic data in context and finding the stories behind the numbers.