Traffic Wales have kindly sent us some more details and a map of the current works on Coryton roundabout.
As you can see in the image above, there will be a new link road connecting the westbound offslip of the M4 to the northbound A470. Traffic Wales told us, “this will remove approximately 60% of the traffic, which currently leaves the westbound offslip and travels around the gyratory to join the A470 north of Coryton interchange.”
Yellow box markings will be added at both ends of the new road and the current traffic signal system will also be “upgraded and reconfigured to suit the new traffic flows.”
Traffic Wales will post further updates on their website.