You need to get a four wheel alignment check done(not just tracking) on the car as the first action. Only this will tell you if there is something wrong with the the wheel setup, or god forbid the chassis of the car.
Anything else will just be guessing.
It could be that the toe or castor is out of spec, suspect camber wouldn't cause tramlining.
Admittedly those tyre pressures seem way too high, but if you had them set lower previously and still experienced tramlining then the issue is still there regardless of pressures. I also used to drive the A12 from Witham to Brentwood daily and never experienced bad tramlining.