The Highways Agency said the outstanding minor works at the new Bowdon View Bridge scheme will be finished and all lanes open by Friday 27 May.
An update issued by the HA said: "Connection of the signals over the lanes is yet to be completed as is the completion of the top soiling and grass seeding. For safety reasons, the newly provided additional lane on the westbound carriageway remains closed until the works are wholly complete. This work should be concluded by Friday 27 May 2011 and will be open in time for Bank Holiday weekend."
The HA said there would be some off peak day and night time lane closures in order to finalise the connections to the electronic signs and allow for testing and residual works.
The busy commuter route between east Cheshire and south Manchester has been disrupted intermittently for a year whilst the work to replace the M56 Bowdon View Bridge has been carried out.
The HA said: "We have worked hard to replace the structure in the quickest time frame possible with the least amount of disruption to the travelling public. We would like to thank you for your patience during this time."
The update statement added: "The current phase of the scheme is to carrying out improvements to M56 Junction 7 westbound diverge. The M56 Junction 7 is a strategic link for vehicles joining the M6 southbound via the A556 and experiences congestion during peak periods. The work has included the conversion of a length of the westbound hard shoulder to a running lane on the approach to Junction 7, effectively making the dedicated exit slip two lanes wide, leading from the three lane main carriageway and up to and over the new two lane bridge."