Campaigners fighting a 5 million sq ft rail terminal on the outskirts of Northampton say they are 'disappointed' they will not know the Planning Inspectorate's views on the plans before a decision on them is made.
The public examination into the proposed development on farmland adjoining Junction 15 of the M1 ended on April 9.
The Planning Inspectorate is expected to send its recommendations to the Secretary of State for Transport on July 9, with a decision expected from the relevant Minister within three months.
However, local authorities and affected communities will not know what recommendation has been made on the scheme - by developers Roxhill - until the decision is announced.
Rod Sellers from the Stop Roxhill Northampton Gateway Action Group (SRNGAG) said: "It is disappointing that the final recommendation of the Planning Inspectorate will not become public until after a decision is made by the Government minister.
"There will, therefore, be little opportunity for local communities to respond effectively to what, in the end, will be a political decision."
Campaigners say the plans for a giant Strategic Rail Freight Interchange and warehouses - known as the Northampton Gateway scheme - would inflict 'enormous environmental damage' on a 500-acre swathe of countryside and create gridlock on a vast road network surrounding it.
SRNGAG also say the plans conflict with national and local planning legislation as the West Northamptonshire Joint Core Strategy - a planning blueprint that is meant to determine what areas of land can be used for - excludes this site for industrial development.
The proposal is opposed by 30 parish councils surrounding the greenfield site including Milton Malsor, Collingtree, Blisworth, Roade, East and West Hunsbury and Grange Park.
It has also been opposed by the MPs Andrea Leadsom and Chris Heaton-Harris, as well as Northamptonshire County Council, which believes the local road network "is already far too congested to accommodate these schemes".
Northampton Borough Council wrote last year to the Secretary of State asking for an urgent review of the policy guidelines governing the location of Strategic Rail Freight Interchanges given that DIRFT - a massive interchange in Daventry - is located only a short distance from the proposed site.