It was due to be one of the crowning moments for London 2012 Olympic Games organisers after years of painstaking planning and organisation.
The Daily Telegraph can disclose that the clock supplied by Omega, the official Olympics timekeeper, has only been set to a general time of 7.30pm, not an exact opening ceremony time.
While organisers have yet to decide the start ceremony’s start time, it is understood three scenarios are being examined – 7pm, 8pm or even 12 minutes past eight, which would be digitally represented as 20:12.
On Tuesday, ticket applicants were urged to visit a Lloyds TSB branch where they could fill out a paper application form and then pay by cash, card or cheque.
There is a six week lottery period, to April 26 at 11.59pm, for fans to apply. Ticket sales are expected to generate more than £500 million in revenue.
Tickets would be available if applications were completed before the deadline. Payments are not taken on successful applications until around June.
Prices range from £20 a seat for preliminary sporting rounds to more than £2000 for the opening and closing ceremonies.
Games organisers have said that at least half of the Opening Ceremony tickets will be made available for the general public.
But officials warned sports fans not to rush to make their online application because it was not a “first-come, first-served system”.
The majority of Olympics tickets will be sold in a ballot, giving every applicant an equal chance of attending an Olympic event. Corporate hospitality packages for the games are being sold for up to £4500 a person.
A London 2012 spokesman insisted there was “no glitch” with the ticket website. He said the system did not have any major feared computer crashes.
“The expiry date is made clear in all of our materials – if your Visa card expires before August 2011, you will not be able to process your application,” he said.
"Visa is working to extend this to allow more people to apply. It is being sorted.”
He added about the clock: “A decision had to be made when to start the clock and it was agreed that 7.30pm was a time when the world would be focused on London, even if the opening ceremony starts a little later.”
The online auction website eBay has announced a crackdown on ticket touts.
Figures show there are about 100 million Visa credit and debit card accounts in Britain. Visa declined to say how many customers this affected.