While there is no official word on whether HSBC will abandon Buffalo’s tallest building, all signs are there and therefore the warnings must be heeded.

As reported by The News’ Jonathan D. Epstein, HSBC Bank USA President and CEO Irene Dorner held a routine conference call with her senior managers last week and indicated that all employees will be leaving One HSBC Center by next October. The bank announced just this week it is laying off about 60 workers, most from the tower.

Calling it a mass exodus if the bank does vacate the building is an understatement. The bank leases about 78 percent of the 38-story, 850,000-square-foot structure.

The building is already losing its next two biggest tenants. The Phillips Lytle law firm, which currently occupies four floors, will move by late 2013 into the former Donovan State Office Building, which is being renamed One Canalside. And the Canadian Consulate, which took up two floors of the tower, has said it will reduce staff here to two full-time employees.

Those two moves alone are enough to raise concern about what to do with a potentially vacant white elephant sitting in Buffalo’s downtown.

Let’s just say it’s good to see the owners seeking input from a well-respected source as to how to repurpose One HSBC Center.

The New York City-based partnership known as Seneca One Realty LLC is looking to the team of experts from the national Urban Land Institute. As reported, there will be a panel discussion and a study of best possible uses. The study will be partly funded by Buffalo Urban Development Corp., an economic development agency.

The ULI, based in Washington, D.C., has already earned impressive grades here for its work in helping devise a creative reuse for the former Millard Fillmore Hospital at Gates Circle. And earlier this year, institute consultants unveiled a plan to repurpose vacant parts of the Rainbow Centre in downtown Niagara Falls. The old shopping mall would be dramatically transformed into a public square with streetside shops, a farmers’ market, a bowling alley and a movie theater.

The institute’s planning experts are gathered from all over the country and have demonstrable skills in Rust Belt revitalization. Their input will be eagerly awaited, whether the result includes offices, condominiums, apartments or hotel rooms. A residential conversion would reportedly cost four to five times as much as refurbishing the space for another office user, but the question then becomes where to find another office user for the enormous space.

Again, there has been no official word on bank officials’ plans for its 3,000 local workers, but it’s hard to ignore the fact that it has sold its upstate branch network, credit card business and mortgage operations, and then a couple of years ago began saying it might not stay in its namesake tower.

Allowing One HSBC Center to sit empty and idle would be a disaster for downtown and the city as a whole. Finding meaningful reuse for Buffalo’s tallest building is mission critical, and fortunately the owners are reaching out for help.