For nearly three years, the 139-unit condo development at 555 Fulton St. in San Francisco’s Hayes Valley has been “coming soon.”

Yet, despite spurts of work at the site, “soon” never seems to come.

In the 33 months since the developer, Fulton Street Ventures, pulled a building permit for the condos, much taller projects around the city have sprouted and attracted occupants: 300-unit complexes in Mission Bay, office buildings in SoMa, 40-story towers on Rincon Hill.

But the five-story building project on Fulton Street has languished even though such a development typically would take about 18 months to put up.

City officials say that some of the delays have been caused by the developer, Fulton Street Ventures, a subsidiary of the giant Chinese builder R&F Properties, redesigning aspects of the project midstream, without city permission, after it had been approved.

Approximately 30 of the 80 condo buyers who signed up for units have walked away from their contracts because the project is so far behind schedule, according to market sources.

Ordinarily, such delays would just be a mild inconvenience to neighboring residents, who have to live with the noise and lost parking spots during construction. But in the case of 555 Fulton, the holdup means postponement of something the neighborhood has long coveted: a full-service grocery store.

Supervisor London Breed, who represents the neighborhood, spent years working to bring a grocery store to the site. She successfully introduced and got passed legislation allowing retail chains on the site — something that is banned in Hayes Valley. She worked with the neighbors to select and then recruit a tenant for the space: New Seasons Market, an Oregon grocery store that recently opened its first California outpost in San Jose.

“We were pleased and more than thrilled when we found out about New Seasons,” said Jacque Henderson, secretary of the board of the Ammel Park Cooperative Homes, an affordable rental development across the street from 555 Fulton St. “We need fresh food — not packaged.”

But more than a year after news leaked out that New Seasons had tentatively agreed to occupy the space, the store is no closer to opening.

“Everybody has been at a loss to understand what’s happening, and everybody is frustrated,” Breed said. “We have been dealing with communication challenges and a difficult developer.”

According to the city, the developer’s midstream changes to the project led to the builder ordering a glass curtain-wall system that was different — an import from China of lower quality — than the Planning Commission had signed off on.

The discrepancies came to light in August 2015 when city planner Claudine Asbagh took over the project. She was reviewing an addendum to the plan — typically a technical clarification or slight modification — when she noticed that the developer had radically changed the original glass exterior and had eliminated the landscaping and streetscape improvements.

That was highly unusual — and a big problem.

“We contacted them to let them know that the department would not be supportive of the changes,” she said. “If they wanted to go through with them they would need to go back to the Planning Commission.”

After lengthy negotiations in February, Fulton Street Ventures agreed to go back to the originally approved exterior and streetscape. But that meant that the developer had to order a new curtain wall system — this one fabricated in Mexico — which took several more months to arrive. Altogether the construction problems stopped progress for more than a year.

“It’s a hugely important site, and we want to make sure the community gets what was approved,” Asbagh said.

Meanwhile, residents are awaiting news on what impact the delays will have on the grocery store. Alan Mark of the Mark Co., which is handling sales for the developer, declined to say when the project would be completed or if the grocery store is still committed to the property. He said the ownership — which is also acting as general contractor — would not comment on how many units have been sold.

New Seasons also would not comment on whether it is close to signing a lease or when the store could open. “We are still very interested in the location, as we always have been,” said Jerry Chevassus, chief development officer for the grocer. “We’re working it.”

Gail Baugh, president of Hayes Valley Neighborhood Association, said the site is geographically important as it straddles the border of Hayes Valley, which has experienced gentrification, and the Western Addition, which is home to a number of low-income housing developments and recent immigrants, in particular from Ethiopia and Eritrea.

While most of the new high-end condos that have popped up in Hayes Valley over the past few years have offered little for longtime residents, 555 Fulton could knit together neighborhoods divided by a wide income gap, Baugh said.

“We see the grocery store as a gateway, a portal,” Baugh said. “Food brings people together. We know that. We all agreed that an affordable grocery store in a food desert was the most important thing we could do on that site. ”

The good news, Baugh said, is that the project seems to be back on track. The glass exterior has started going up over the last few weeks. Baugh is hopeful that New Seasons will sign a lease as soon as the skinning is complete.

“A lot of people have worked really hard to make sure the developer doesn’t screw this up,” she said.

J.K. Dineen is a San Francisco Chronicle staff writer. Email: jdineen@sfchronicle.com Twitter: @sfjkdineen