Aberdeen bypass construction partner Galliford Try has said the practical completion of the project is due this summer but it expects to face additional costs due to delays.
The Aberdeen bypass was due to be finished by the spring.
Galliford Try and Balfour Beatty are now covering the costs after former bypass partner Carillion went into liquidation in January.
Galliford Try expects weather-related additional costs of less than £25m.
The £745m 28-mile bypass is one of Scotland's biggest infrastructure projects.
In a statement to MSPs earlier this year, Economy Secretary Keith Brown said the contractors were pushing for a late August deadline.
However Transport Scotland advisors have suggested it is prudent to aim for a late autumn opening date.