The three-month closure of a busy slip road is being extended until the new year – and a reduced speed limit is also set to come into force.
The entry slip will be closed for longer to enable construction of part of the bridge.
Kent County Council (KCC), which is overseeing the work, is yet to confirm a timeframe for when it will reopen.
These closures are under way as part of the £32.7 million revamp of the Grovehurst junction which was given the green light by county councillors in March 2022.
The scheme is using the existing bridge but will replace the dumbbell design with a new one-way gyratory system incorporating a second bridge.
It will be built on the Sheppey side of the roundabout and include a cycleway and footpath linking to Iwade.
The bulk of the funds are coming from a £38.1m grant from the government's Housing Infrastructure Fund (HIF). The rest is being paid for with contributions from housing developers.
In August, it was confirmed by KCC that the A249 Grovehurst junction Sheppey-bound exit and entry slip roads would be closed until December 2023.
Currently, parts of the A249 towards Sheppey by the Grovehurst roundabout are down to one lane.
Earlier this month the A249 was reduced to one lane Maidstone-bound towards Stockbury, between the Cowstead Corner roundabout on Sheppey and the A249 at Grovehurst after work started on Friday, October 13.
It was in place for several weeks and caused a number of headaches for both commuters and residents and led to hundreds of pupils arriving late to school after sitting on buses for more than an hour-and-a-half.
It reopened on November 15 and is now set to be rephased so construction of the new bridge at the Grovehurst junction, which requires a lane closure of the Maidstone-bound carriageway, will start in early January 2024.
Following the removal of the lane closure on the Sheppey Crossing Maidstone-bound, it has emerged National Highways intends to lower the speed limit from 70mph to 50mph from Cowstead Corner, across the bridge, and towards the Grovehurst junction.
A public notice read: “The effect of the variation would be to extend the northern end of the current 50mph speed limit on the southbound carriageway of the A249 to its exit point from the A2500 roundabout.
“The variation would come into force on December 15.”
National Highways was unable to comment on the speed limit change.
A KCC spokesperson said: “The works to build the highway improvements at the A249/ Grovehurst road junction will require complex traffic management planning.
“The closure of the northbound slip roads will be required on several occasions throughout the works to enable the safe construction of the improvements.
“The original notification for the first phase of the works was for the northbound exit slip road until December 2023 with the northbound entry slip road having a duration of 30 weeks from August.
“The contractor is currently reviewing the strategy for the next phase of the works and will provide an update on future traffic management requirements, once agreed with KCC Highways and National Highways.”
For the latest travel and traffic news listen to kmfm.