The bypass opened last August but part of it was closed to traffic when a weak embankment near Eye Green caused cracks in the road.
Lincolnshire County Council said it hoped to recoup the £5m cost of fixing the problem from “third parties” but said it could not elaborate further.
William Webb, council member for highways, told the BBC: “It was hugely disappointing for us and highly frustrating to the villagers of Eye Green.”
The council said the exact opening date would be determined by weather conditions as work is completed over the next few weeks.
Morgan Sindall was main contractor on the bypass job jointly run by Lincolnshire and Peterborough councils.