Starting in mid-2020, a £25.8million project aimed to widen 2km of single-carriageway to accommodate an extra lane in both directions.
The mammoth task, which involved controversially clearing large amounts of vegetation from the roadside, was scheduled for completion by the autumn of 2022.
However, pictures – taken on the Angmering Bypass last week – show there is still a way to go.
A West Sussex County Council spokesperson said: “The A259 improvement works at Angmering and Wick are progressing well, with much of the second carriageway foundation in place, having already built most of the first carriageway.
“The A259 is a strategically important corridor for utilities, with high-pressure gas mains, trunk water mains, lots of telecoms cables and high-voltage electricity power lines.”
The council said ‘much of this apparatus was ageing’ and ‘needed to be moved and replaced’ outside of the footprint of the new road.
"These works could only be done by the utility companies themselves, and so a large part of the job has been co-ordinating and facilitating these activities,” the council spokesperson added.
"As a result, the pace of the works has been largely dictated by the utility diversions, with the last major connection having been made at the new roundabout in Wick in mid-June.
"These works took longer than expected, which has had a knock-on effect for the forecast completion date, which has moved into early December 2022.
“With the utility works now substantially completed, we should have a clear run to complete the scheme and we would like to thank all road users for their patience while these improvement works are ongoing.”
Click here to find out more about the scheme.