Ford Mondeo IV Titanium X Saloon 2008 - Uneven rear tyre wear - WotNotAgain

I'm shocked to find that the rear tyres on my 2008 Mondeo Titanium X Saloon hve worn unevenly. I had to replace tham after 30,000 miles. The outside of the tyres were bald and the inside has still 4mm or so of tread - any known solutions?

Ford Mondeo IV Titanium X Saloon 2008 - Uneven rear tyre wear - piston power

Four wheel alignment to check but 30k is good for rear tyres.

Ford Mondeo IV Titanium X Saloon 2008 - Uneven rear tyre wear - NARU
My (mk3) mondeo used to get 45k out of the rears.

I agree that a four wheel alignment check is the first start
Ford Mondeo IV Titanium X Saloon 2008 - Uneven rear tyre wear - boggles

Had a quick google around and the rear tracking is adjustable on the Mondeo. As the outer edges are going, you have too much toe in. This is adjusted by cam bolts on the outer end of the rear wishbones. It seems to be a common problem, and some cars have been done a couple of times before getting it right.