Crowdfunding site Indiegogo has called time on a high-profile British project to create a retro handheld console.
The US firm has told backers of the Sinclair ZX Spectrum Vega+ that it is appointing a debt collection agency to recoup funds from the London-based company behind the campaign.
It said Retro Computers Ltd (RCL) had failed to meet the conditions it had set to be given more time.
RCL told the BBC that the intervention was "highly destabilising".
"Indiegogo asked for proof that we are ready to ship the product and requested that we send them a unit to their San Francisco office," added Dr David Levy, RCL's chairman
"We responded yesterday saying that we would sooner give a demonstration of a unit to their UK representative, and asking Indiegogo to request that he contact us to fix an appointment. Their reaction was this latest statement."
He added that RCL was "still determined to deliver to backers and have this morning received a number of messages from backers asking us not to give up".
Indiegogo had warned RCL in February that it planned to retrieve funds if deliveries had not been made by the end of May, but subsequently had offered a fortnight's extension.
"The campaign owners have not met the requirements Indiegogo sent last week," a spokesman for Indiegogo said in a statement.
"Our Trust & Safety team is now continuing the process of sending this campaign to collections in an effort to return funds to backers.
"During this time, the campaign owners are still able to pursue fulfilment of the project and they are not prevented from shipping any units that are ready to be sent out to backers."
The Vega+ campaign raised a total of £512,790 from more than 4,700 people on Indiegogo before the US firm blocked it from accepting more funds in March 2017.
In addition, RCL has claimed that "pre-orders" for the games machine have been "selling fast" via its own website.
'Oil on flames'
Last week, Dr Levy said that he intended to send out the first units by 15 June.
However, he signalled that this goal was now in jeopardy.
"Indiegogo have seen fit to make this and earlier statements which have poured oil on the flames and made it more difficult for us to deliver the Vega+ project," he said.
"Far from helping their backers to receive the Vega+, Indiegogo's statements have had the opposite effect, by worrying some of our suppliers."
RCL has missed multiple deadlines over the past two years and given a variety of reasons for doing so, ranging from problems with the buttons of the Vega+ to disputes with former company directors - the details of which are contested.
The company had originally pledged to deliver the console in the summer of 2016.
Indiegogo had given three conditions for it to postpone a the threat of intervention, which it had made in February.
- RCL had to courier over a final production unit by end of day Tuesday to prove its existence
- the firm had to refund any backer who no longer wanted to receive the console
- the company had to provide contact details for representatives at Sky who supposedly were delaying the consoles being sent out
Sky does own some of the intellectual property rights involved, since it owns Amstrad, which acquired Sinclair's marketing and merchandising rights in 1986.
RCL previously signed a contract with Sky promising to provide it with a working version of the Vega+ for quality checks, but a spokeswoman for the broadcaster said it had yet to receive it.
She added that Sky did not believe it was to blame for any delay in the console's release.
"We would love to see these consoles in the hands of fans, that's why we gave RCL permission to use the Sinclair and ZX Spectrum branding on the console in the first place, despite the fact there will be no financial benefit to Sky," she added
"However, we have yet to receive a final working version of the console from RCL."
According to RCL's most recently filed accounts, it had £433,008 of assets at the end of March 2017.
As yet, Dr Levy has declined to provide an update.
A website campaigning for Sir Clive Sinclair - the original inventor of the ZX Spectrum computers - to intervene has identified 120 backers who say they have requested refunds.
It says that they have requested a total of £14,760 be handed back.
What powers do debt collectors have?
While the involvement of a debt collection agency will escalate matters, it will not necessarily bring them to a close.
Unlike bailiffs, such agencies cannot seize assets themselves. In past cases, some companies have simply opted to ignore them.
When this has happened, the agencies have sometimes had to pursue legal action on their clients' behalf.
And only when they won have enforcement officers been appointed with the power to confiscate property.
Bearing in mind that backers neither have a stake in RCL nor have they bought something in the traditional sense - rather they funded an endeavour - it is not clear how a judge would rule were Indiegogo to pursue this route, or even if the dispute would get to court in the first place.
"This is a complex and difficult case," commented Peter Wallwork, chief executive of the Credit Services Association.
He added that even when companies are forced to hand over funds, the effort required often involves "additional charges that would have to be met by the debtor business", eating into the sums recovered.