That waveform is the classic 'unstick' routine for a jammed turbo actuator, the DTC will be set after the routine is completed and either the current is excessive or the commanded position is unreachable. The fuelling will be excessive as it doesn't have a fuelling map for low 0r no boost.

The wave routine in the picture was peaking and troughing as the throttle was being blipped. If I held the revs stationary the commanded position went to a flat line as per the end of the graphs. It did the same but at a different position if I let it idle. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Ah right - this is actual values not the ECM's interpretation. You can see the 'unstick' activity.

Interesting.

It’s the IID Bluetooth tool that I’m using. I’m not sure of it’s limitations.

The fault code on this car relates to the NS turbo, if that one was sticking would it stop the drivers side one operating correctly? Are they linked across the intake or are the independent of each other? 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Well there's two separate fresh and charge air paths but they both end up being shared across the plenum,
I think it's more a question of what the engine protection strategy is in the event of a stuck turbo actuator, most fail in the minimum position but there would need to be some protection if one jammed 'on boost', most likely it is detection of boost demand/actual correlation followed by commanded position not achieved, it would make sense to reduce activity on both turbos in either event.

Thanks Phoenix,

I'll need to try and figure out how to get into the NS turbo I think. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Been doing some reading tonight and have found these 2 threads which are a huge help:

Actuator Access - https://www.fullfatrr.com/forum/topic41533-15.html

Turbo Waste Gate - https://www.fullfatrr.com/forum/topic35415.html?highlight=turbo

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Pleased to report I managed to find the passengers side actuator. You need to look through this oval hole:

Click image to enlarge

Excellent!
The next thing to do is make sure it gets a good, 'energetic' drive to work the actuators with a good bit of heat around to dry out any remaining corrosion and wear it smooth.

A lot of my 'special tools' are made from TiG rods or stainless steel brick ties...

Thanks Phoenix.

Few jobs to do before we get to that stage unfortunately but I’m just glad that it’s running properly and making boost again now.

Will give it a good warm up and service too so there’s fresh oil going around the system. Is there anything worth doing to “help” a turbo get going again after it’s been parked up or are you as well just getting fresh oil into it and leaving it be?

David. 2002 4.6 Vogue SE - Alveston Red with Lightstone Leather
2012 Range Rover 5.0 SC Autobiography in Indus Silver with Jet/Ivory Interior
2012 Range Rover 4.4 TDV8 Autobiography in Baltic Blue with Sand Interior

Fresh oil, heat and use are the best reconditioners for engines, I've seen a few rebuilt engines from various 'classic' (i.e. old and mostly unloved) cars rebuilt at great expense, then parked up and ignored for 11.5 months, then suddenly expected to perform like a daily workhorse, with predictable results.
It may be worth double-dosing with some fuel improver (Dipetane is my choice) to help clean up the engine or adding no more than 1.5 litres of Kerosene / AVTUR / Jet A-1 to a full tank of diesel to increase burn temperatures and burn off accumulated carbon in the cylinders and exhaust.