I've a seized turbo actuator and no amount of abuse and penetrating oil can get it moving even a bit. I'm guessing that sitting around in a damp environment (my hill in Wales) has really frozen it in place. Anyway... Its going to a local LR specialist (Not Paul HughN!) in a couple of weeks to have the body lifted and the turbo checked/reconned/replaced as necessary. They're going to do the rear belts and fix the a/c at the same time. Rear brake pipes were mentioned but they were spliced out with copper ones a while back, so probably ok.
Anything else worth doing whilst its up in the air?

Loosen and tighten the top mount nuts for the struts? If you need to replace the struts, not having them seized from a decade plus of crud would make the job easier. With the body off, access to the nuts is simple.

Check the crossover pipe? If it's looking dodgy, replace it as that's a body off job anyway. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed

Hopefully getting back this week.

Turbo veins choked up with crud, new a/c condenser & some ARC pipes + belts on the engine.

when my turbo went in my l322 - I purchased 2 off ebay and got the garage to change both while the body was off 2016 Range Rover Sport SDV6 autobiography (MY17)
2017 Range Rover Velar First Edition SDV6
2015 Range Rover Sport Autobiography 4.4
2012 Range Rover Sport SDV6 HSE Luxury Black

When mine was body off to replace the crossover pipe, I had them replace the fixed brake lines that run along the chassis. Easy peasy with the body off. 2012 SDV6 - it's missing a couple of cylinders
2008 TDV8 - it was a labour of love and is much missed