Songtheows seem to take different route options depending on traffic conditions. If you going to Dogtarn it's better just to get off at the Jomtien Complex and walk. You have to cross Thappaya and traverse the ditch and walk around the heavy equipment.
I went by this construction project on four days (1-4 March) and there was no one working. Heavy machines parked in the excavated ditch. Lets hope they return to working soon.

Also 13/4 is closed for some sort of road work. Did they not just finish this road?

It might be easier to list the roads that are passable and not under construction in Pattaya.