Five months after it first hit the press, U.S. owners of 580,000 diesel vehicles with Volkswagen TDI engines are no closer to knowing how or when their cars will be modified than they were in mid-September.

And if a report last week by the Reuters news service is accurate, they have at least another month to wait--and potentially longer yet.

VW Group has said it will issue the results of its internal investigation into the diesel-cheating scandal on April 21, although that report is separate from any agreement with the EPA.

DON'T MISS: VW To Release Diesel Cheating Report April 21, Annual Meeting Postponed

That day in April was originally when the huge global automaker planned to hold its annual investors' meeting, which it has now postponed--an unusual move indicating just how seriously the scandal has affected its finances and future.

Now a report in Germany's Manager Magazin, as cited by Reuters on Friday, suggests that no agreement between the U.S. EPA and Volkswagen will be reached until at least the end of March--perhaps later than that.

2014 Volkswagen Passat TDI

2014 Volkswagen Passat TDI

That date is attributed to "company sources," who told the magazine that "top managers at Volkswagen" don't expect any settlement before the end of next month.

It also said that the delay is due, in part, to an EPA demand that proposed modifications to the various diesel models affected undergo long-distance testing for durability before the agency will consider approving them.

ALSO SEE: EPA To Demand More Electric Cars From VW To Settle Diesel Scandal: Report

Meanwhile, it said, the costs to VW Group for modifying more than 500,000 vehicles, or perhaps buying back some of them, and settling dozens of lawsuits across dozens of jurisdictions will be "significantly higher than previously expected."

A report yesterday in the newspaper Welt am Sonntag suggested that the EPA wants Volkswagen to help fund a nationwide DC fast-charging network for electric cars and commit to building an electric vehicles at its assembly plant in Chattanooga, Tennessee.

2015 Volkswagen Golf TDI driven to all 48 contiguous states with just $300 of fuel

2015 Volkswagen Golf TDI driven to all 48 contiguous states with just $300 of fuel

Volkswagen consistently declines to comment on the progress of negotiations with the EPA and its partner, the powerful California Air Resources Board.

Last month, the board rejected Volkswagen's first proposal to modify its non-compliant diesel cars as lacking detail on the fuel-economy and performance impacts of the changes.

MORE: How Will VW Fix My Diesel Car, And When? A List Of All Models

Owners of the TDI vehicles from Volkswagen, Audi, and Porsche remain in limbo, with the values of their vehicles having plummeted and rampant uncertainty about the nature, extent, and timing of the changes.

The process of updating the cars will likely take more than a year even after all parties agree on a final plan and any necessary parts are ordered.

Volkswagen, Audi, and Porsche have all suspended sales of all new and Certified Used TDI diesel vehicles, though non-certified used models remain available through various sellers.


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