Back in June, London-based Benson + Forsyth cracked open the bubbly after being told by the RIBA's competition office that it had landed first prize in the Beamish Visitor Centre contest.
But it now appears that the impressive victory, which saw the practice beat the likes of Kengo Kuma, Richard MacCormac, Stephen Hodder and Ted Cullinan, is in peril.
Those planning to fund the museum have dramatically decided to vote on whether or not to uphold the jury's decision to select the contentious Modern design.
This reassessment has been greeted with dismay by the Competitions Office, which issued an angry statement on Tuesday (26 September).
And another source close to the selection process said the move to 'ratify' the winning scheme was 'making a mockery of the whole competition' and could potentially jeopardise funding of the 'vision project' from backers such as bank Northern Rock.
Despite what was described by a jury insider as a 'fairly overwhelming vote' in favour of the Benson + Forsyth design, the firm will not know if the jury's 'absolute' decision will stand until after a meeting of the Joint Committee for Beamish in November.
This committee comprises the seven key stakeholders in the open-air industrial and agricultural museum, and is chaired by Sunderland councillor Mel Speding, who was also on the jury.
Worryingly for Benson + Forsyth, Speding did not vote in favour of the winning scheme and has recently admitted that he does not believe the appointment is 'cut and dried'.
It is understood that one of the issues which will also be discussed by the committee is the opinion of the museum's founder, Frank Atkinson, who said the 'ultra-Modern' design was not in keeping with the rest of the historic buildings.
The decision to re-evaluate the Benson + Forsyth scheme has enraged the RIBA Competitions Office, which has been unable to publicly announce the winner because of the uncertainty surrounding the result.
In a statement released to the AJ, the Competitions Office said that Beamish was well aware of the expectations about appointing a clear winner when it signed up to the competition process in January 2006.
A spokesman said: 'The RIBA is extremely disappointed by Beamish's delay in appointing Benson + Forsyth.
'We are deeply concerned that this continued delay reflects unfairly on the selection process (which was open and transparent), the integrity of the jury panel members, the RIBA Competitions Office and, above all, does a great disservice to the teams who took part in this competition.'
Benson + Forsyth was unavailable for comment.