The boundary marked on plans for a huge rail depot near Northampton is not set in stone, developers have said.
A map showing the area that Ashfield Land is interested in between Blisworth and Milton Malsor has been widely circulated among concerned villagers.
The boundaries to the south, east and west are understood to be non-negotiable.
But the developers have now said the red line is simply the maximum limit of the scheme and that there is a chance the northern boundary, near Milton Malsor, could be changed as part of the public consultation.
Claire Cope, of Ashfield Land, said: “The red line that people have seen is the area of technical study.
“I wouldn’t want people to think the site will be half the size or anything like that.
“But there is opportunity for discussion through the consultation about where that boundary [to the north] will be and what people might like to see in that area.
“It’s not necessarily that same red line that will appear in the final version, in the development consent order.”
If approved by the secretary of state, the site would become a giant rail depot with warehouses covering an area the size of about 100 football pitches.
People living between the villages have expressed concerns about the future of their homes.
Ashfield Land said the scheme will create 8,000 jobs
A public consultation is set to begin sometime in April.