The tender documents, which were published a day earlier than intended, were supposed to be launched by English Partnerships tomorrow (Friday).
All shortlisted entrants will be expected to take part in a national exhibition and the winners will be asked to engage fully in local and national discussions about their design and methods.
The winning developers or house builders -EP wants more than one - could build up to 1,000 homes with supporting infrastructure on sites in the East Midlands, East of England, Yorkshire and the Humber and the South East.
A minimum of 30 per cent of the housing units will be built to the target cost, with the remaining units built to equivalent cost efficiency standards. Firms are not expected to use particular supply, procurement, materials or delivery methods.
Firms must express an interest to EP by May 13 and selected firms will be asked to deliver their proposals by July 1.