Two Moriches sisters whose plan to open a Dairy Queen in Medford was nearly torpedoed by last-minute objections by PSEG Long Island say the utility has withdrawn its complaints.

Co-owner Michelle Robey said the utility on Thursday gave written assurances rescinding a cease-and-desist letter that froze her bank funding and halted construction on the project for more than a month, delaying a planned fall opening.

“I’m very relieved it’s been resolved but still perplexed as to how it could happen in the first place,” Robey said.

A PSEG manager “apologized for everything that has transpired,” she said in a note.

PSEG spokesman Jeff Weir said, “We were eager to work through all the issues with them so they could get back to work on their project as quickly as possible.”

Robey said excavation crews were back on site Thursday.

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“It looks like it’s a go,” she said. “It’s very exciting. They’re moving dirt on the site today.”

Robey and her sister Patricia DeMint worked for years on their dream of opening the DQ Grill & Chill restaurant, and finally broke ground in May. Their nightmare began a month later, they said, when they received PSEG’s cease-and-desist letter ordering work to stop because it was “creating an unsafe condition” and violating federal law and LIPA standards.

They were doubly surprised because they’d sent 16 separate notifications about their plans to PSEG through registered mail starting in 2015, and asking if there were any objections. The utility never responded, they said.

PSEG’s Weir said the problem stemmed from a mailroom “processing error” at a Hicksville operations headquarters the utility shares with National Grid.

Weir had said the company was reviewing its processes to make sure the problem didn’t happen again.

“We’re going to review the breakdown in the process that got us to this point and we’re going to ensure we’re going to do everything we can to learn from it,” he said this month.

Robey credited her all-woman legal-engineering team for working round the clock to negotiate with PSEG, including attorney Nicole Blanda of Melville and engineer Jaclyn Peranteau of Holtsville.