Planning Division staff member Todd Draper said Diehl's application is set for a hearing June 12 before the County Planning Commission.
If approved by the commission, the rezoning request would go to the County Council for final approval. Then, if the council concurs, Diehl would go through the county's conditional use permit process for approval of specific elements of his plan.
Exactly what Diehl has in mind if he gets the rezoning is not yet public.
Rezoning applications are not required to include details about intended uses of property, and the forms submitted on Diehl's behalf by Salt Lake City attorney Bruce Baird do not address the future.
They include only a recorded subdivision plat with 43 lots in the area, and affidavits showing support for the rezoning from the owners of 42 of those lots Diehl, who owns 40, and Dominic Dato and Alicyn King, who each own one.
The other lot is owned by Roger Kehr, who has opposed the development's proposed change in direction.
Baird said Friday that plans for Tavaci are fluid because "the economic market has changed so dramatically between last year and now that we are evaluating what to do on the site.
"Other than a continued commitment to protect southern views, like we've always had, there's not any solidity to what will go on," he added. "The zoning we're seeking gives us flexibility to make some reasonable proposals that the county would get to review."
The project has stirred strong emotions ever since being approved by the County Council in 2003.
First, objections focused on a steep access road to the development, most of which is perched on a large gravel sandbar overlooking the valley. Then, after the property became part of Cottonwood Heights with its 2005 incorporation, area residents convinced city officials not to approve Diehl's request to change Tavaci from a gated community with 43 mansions into a multi-use development with 300 condos, hotels, restaurants and retail space in buildings that could be up to five stories high.
Diehl became so frustrated with city planning-process delays that he sued Cottonwood Heights to disconnect from the city. A March 2012 agreement made that possible.
The Salt Lake County Planning Commission is scheduled to hear developer Terry Diehl's rezoning request for Tavaci on June 12. The request involves 47 acres at the mouth of Big Cottonwood Canyon.