(11 Nov 2016, 2:25 pm)tyresmoke wrote Hmm the real problem bit is the A19 flyover between Middlesbrough and Norton rather than north of there but obviously that's going to be a harder one to solve.

It may ease the congestion heading northbound, but can't see how it will help southbound traffic for the reasons you mention. That bottleneck at the flyover is going to be there, whether the Billingham bypass has two lanes or three.