Replacing Subaru tyres

[CaptainSlow]

I need to replace one tyre on my Forester. Treads are circa 4mm all round. Having owned an Impreza for a few years I recall seeing that Subaru recommend replacing both tyres on the same axle to reduce diff damage however having checked the Forester manual it say replace damaged tyres as and when needed and makes no other reference. Any views?

[TXWRX]

i'm sure it would be better to do both on one axle, you probably don't need to though

any idea why one is so worn? might be worth getting the tracking/ alignment checked to see it its been knocked out