After more than three years of design, height and programming changes, Dan Gilbert's real estate company says it is now set to build what would be the second-tallest building in Michigan on the site of the former J.L. Hudson's department store downtown.

At a new proposed height of 680 feet, the Hudson's tower would only be eclipsed in height in Michigan by the 727-foot Detroit Marriott at the Renaissance Center. The new height represents a 25 percent reduction, however, from what was being considered in the fall 2018.

Bedrock LLC CEO Matt Cullen in a Monday interview with Crain's said that programming considerations ended up dictating the new height, which has been in flux since initial plans were revealed for it in February 2017, when it had a tower that was 734 feet, besting the RenCen hotel by a mere 7 feet. It then rose to 800 feet, and then a possible 912 feet, before Bedrock executives last summer began to soften their claims that the building would be the state's tallest.

In January, Cullen told Crain's and the Detroit Free Press during the Detroit Policy Conference that the tower would not be the state's tallest, but didn't know what the precise height would be.

"We're confident (680 feet) is the final answer," plus or minus a few feet, Cullen said Monday.

The current uses include 225,000 square feet of residential space (150 units) and 286,000 square feet of hotel space (200 to 250 rooms) in the tower, along with a 232-foot building referred to generally as "the block" to the north that includes 402,000 square feet of office space, 127,000 square feet of event space and 18,000 square feet of retail space. The tower and the block are to be separated by an activated alley.

"When you look at the program, you say 'what's a high end hotel?' That's 200-250 keys, right? What's the market for residential of this type? You do that and then that defines the program, and then the program obviously defines what you're building," Cullen said.

"And so, I think we've had the opportunity to really refine the program and understand what the market wants, what Dan wants to reflect as far as the characteristics of the building, as far as the quality of the building ... and here's how many square feet we need in order to accommodate that. And then that gets translated into height and width and everything else."

Cullen said there is a March 31 Board of Zoning Appeals meeting during which the company expects consideration of variances to allow a building of 680 feet (instead of the 360 feet currently allowed) in height and 132 feet in width (instead of the 60 currently allowed), and a development with six loading docks, half of the 12 required under city code.

The Hudson's development is now anticipated to be complete in 2023. Foundations are expected to be completed by the end of the month and above-grade building is expected to be visible by the summer. Large cranes are expected to begin being delivered and assembled April 3.

The project has undergone a slew of changes.

At the time of a December 2017 groundbreaking ceremony, the project was expected to be complete in 2022 and have 330-450 residential units; 103,000 square feet of retail, food and beverage space, plus a street-level market; 168,000 square feet of event and conference space; and 263,000 square feet of office space. Another 93,000 square feet of exhibit space was planned, along with at least 700 parking spaces in a below-ground garage.

The first conceptual rendering came in March 2015 when it was inadvertently leaked in a YouTube video discovered by the Detroit Free Press. Then, rumors began swirling about precisely how large the building would be, eventually with multiple sources confirming to Crain's discussions of a building reaching 60 stories in October 2016.

By February 2017, the first incarnation of the plan was revealed, with a tower reaching 734 feet with a total cost of $775 million. In September 2017, another 66 feet were tacked on, bringing the tower to 800 feet, adding a public skydeck (since scrapped) and other features, which brought the project cost to $909 million.

A year later, in September 2018, Bedrock publicly confirmed it was considering an increase in the tower height to up to 912 feet, saying a decision would be made by January 2019 just how tall the building would be. However, up until Monday, a final height had not been revealed.

The architecture firms on the project are Detroit-based Hamilton Anderson Associates and New York City-based Shop Architects PC. The general contractor is Southfield-based Barton Malow Co.

The project is one of four Gilbert has underway that, at the time that a public incentive package was approved, totaled about $2.14 billion. Combined, they received a total of $618.1 million in so-called "transformational brownfield" tax incentives from the state.

The other projects are the $830 million Monroe Blocks project immediately east of the One Campus Martius Building, the $311 million redevelopment of the Book Tower and Book Building on Washington Boulevard, and the $95 million addition to the One Campus Martius building where Gilbert has his Quicken Loans Inc. headquartered.

The Book Tower/Book Building project is expected for completion in 2022 and the addition to One Campus Martius is expected to be completed this year. The design on the delayed Monroe Blocks project is now to finish by the middle of this year, bumped back from the first quarter as was envisioned in August.

Cullen said in January that Bedrock is moving the Monroe Blocks project back in the development sequencing because of the planned Detroit Center for Innovation project announced in October with billionaire developer Stephen Ross, a Detroit native, as well as the University of Michigan. Bedrock expects to prioritize that project, which could top $750 million on the site that was to house the Wayne County Consolidated Jail, over the Monroe project.