The Connector, the lobby and centerpiece public amenity on the ground floor of developer MP Boston's Winthrop Center skyscraper. Banker & Tradesman Staff Photo/Steve Adams

The Boston Planning & Development Agency ordered developer MP Boston to open the centerpiece public amenity of its $1.3 billion Winthrop Center skyscraper on weekends to comply with an agreement with the city.

“We expect you to take appropriate action to ensure the Connector can remain open to the public 7 days a week, as required by the [Jan. 3, 2024 management and operation agreement],” BPDA Director Arthur Jemison wrote in a letter to developers on Tuesday.

In its original proposal to redevelop the 115 Federal St. municipal garage property as an office-residential tower, MP Boston pitched a ground-level “Great Hall” as an alternative to a Prudential Center-type observatory sought in the BPDA’s request for proposals. The developer said the space would become a hub for events from fashion shows to farmers’ markets, and potentially even the mayor’s State of the City address.

Construction of the tower was completed last spring, and MP Boston added five food vendors as tenants in the ground-floor space, now known as The Connector, on weekdays this past January.

But The Connector has remained closed on weekends, which violates a management and operations agreement that requires it to be open at least 16 hours a day, Jemison wrote.

In an emailed response to Banker & Tradesman, an MP Boston spokesperson said, “Winthrop Center has always been a multi-phased project and its hours of operation are contingent on these phases.” In a subsequent email, the spokesperson said the developers needed to speak with the BPDA before commenting further.

The disagreement may focus on the timing of condo sales at the property. The agreement calls for MP Boston to provide an initial operating subsidy of up to $1 million for operating costs, events and programming at The Connector, to cover potential shortfalls. The agreement also calls for a $75,000 annual contribution from the Winthrop Center condo association, increasing with inflation. The facility is expected to eventually become self-sustaining, the document states.

Since its opening last spring, MP Boston has sold 60 of the 317 condos at Winthrop Center, according to transaction data compiled by The Warren Group, publisher of Banker & Tradesman.

The BPDA’s 2020 approval of changes to the Winthrop Center project prompted now-Boston Mayor Michelle Wu to renew her calls as a city councilor to abolish the independent planning and development agency.

The developers successfully requested permission to switch the 317-unit residential portion of the project from condominiums to rentals, citing the uncertain climate to obtain construction financing following the COVID-19 outbreak.

On social media, Wu denounced the decision as a “bad deal” negotiated without transparency.

“The Winthrop Square project was one of my first tastes as a Councilor of how the BRA/BPDA operates; now, some of our worst fears playing out with ZERO public process,” Wu posted on X, then known as Twitter, at the time.

The switch to rentals threatened funding for a 168-unit affordable housing project by the Asian Community Development Corp. of Boston, which had been designated as recipient of $51 million in inclusionary development funds generated by the Winthrop Center project. The switch to rentals reduced MP Boston’s payment to $22 million spread over seven years, and the nonprofit’s designation to develop the affordable housing at 290 Tremont St. expired in 2021. The project was resubmitted last year and is currently under BPDA review.

MP Boston received BPDA approval in 2022 to sell the Winthrop Center residential units as condos, although the developer also has been offering some units under a “rent-to-own” program.

This month, at a ceremony signing an ordinance bringing the independent agency’s planning functions under city hall control, Wu acknowledged the activism of BPDA watchdogs including Steve Hollinger. Hollinger has used his FortPointer social media account to publicize alleged failures of developers to live up to their agreements with public entities, including the Connector’s hours of operation.

“I want to shout out Steve Hollinger, who has been probably more immersed in the details of planning at the BPDA than anyone in the city over a decade,” Wu said at the event.