OFC's collapse in April last year is being investigated by the Serious Fraud Office after much of the pounds 22m invested, with the promise of fantastic returns, disappeared offshore.
The rescue, however, has faltered over fears that the deal gives investors less control of their birds than under the OFC.
They have now been given 10 more days from last Friday to decide whether to accept or not.
Under the deal, they are required to swap ownership of their ostriches and pay an extra 13 per cent of the value of their birds for shares in a UK-based company, Belautruche Ltd.
That firm, in turn, will have the rights to buy up to half of Belautruche NV, a Belgian company controlled by ostrich farmer Eddie Nachtergaele, which will actually own the birds.
Mr Nachtergaele is currently looking after 2,179 birds on his Belgian farm and is threatening to take possession of them over unpaid bills.
As the original deadline passed on Friday, the directors of Belautruche Ltd admitted they were "a few thousand pounds short" of the minimum amount and were not expecting to raise the pounds 2.8m needed to buy the full half of Mr Nachtergaele's company.
"We have had a lot of requests from investors living overseas for more time since some of them only just received their prospectuses," said General Sir Robert Pascoe, chairman of Belautruche Ltd and himself a victim of OFC.
Sir Robert added that between 700 and 800 people had accepted the offer. A further 1,000 remain undecided, while others have rejected the scheme.