Well it seems lady luck has shined upon me which doesn't happen very often!!
Rodger, at Clarkes had the car back yesterday and did a forced regen. Apparently in 800 regen attempts it had succeeded with 100. He said the car drove perfectly with no smoke. The soot level went down just as it should and 'ALL' the sensors are working.
He explained to me that some cars/engines can fire out masses of smoke and soot especially those that only require a static regen.
He also took off the intercooler hose which only had a drip of oil in it.
I'm going to drain the oil and see what quantity is in there to see if the gauge is reading correctly which might explain the extra oil I've added.
Rodger thinks the sequential turbo might be sticking slightly, which might explain why if I need to accelerate quickly from a junction there is a bit of a lag and the car tries launch itself into the field opposite!!
So I would like to thank you all for your concerns and comments and I'm keeping everything crossed and do all my short journeys in my wife's car.
Thanks Kev.

Glad to hear the good news Kev fingers crossed that it stays that way

That sounds like good news but how do you explain loosing 3L of oil. I'd remain cautious but optimistic  2012 TDV8 Vogue (L322)

Roger to the rescue! Family use Clarkes and are very impressed with their service and knowledge! (Less so for Roean btw!)
Keep us posted!
PS There are some places that do DPF and EGR deletes on these  Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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Roean says there isn't a turbo drain mod, they even rang Land Rover Direct who also told them there isn't one!!!! We know more than the so called experts mate.

There you go! Has yours had it fitted out of curiosity? Roger will know 👍 Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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He couldn't tell me unfortunately. I thought he would. He says there is newish sealant around the lower core plug though.
I'm gonna have a look myself now I know where it should be.

Glad to hear you are making progress with the problem Kevin.

I would be interest to hear how much oil you drain out .

All sounds promising though. Good stuff !

Andrew.

Update, the car is still going okay. There is still a puff of smoke when the second turbo hasn't been used in a while but no smoke if used again over the next few miles/days.
I drained the second sump today and perhaps half a litre came out.
I've managed to look at the turbo drain pipe and it hasn't had the mod.
Gonna get a few quotes to see who will take the job on.

Green Oval is a great company and know their stuff with this mod, they did mine and it completely resolved the issue. Mine resembled a James Bond movie when overtaking etc if it hadnt stretched it's legs for a few miles, absolutely horrendous. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

Save yourself a load of cash and risk with the turbo drain mod by simply booting it above 2500rpm regularly when warm  Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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Until it dumps enough oil in there for diesel runaway and then youre royally screwed. BMW i3 Electric Car
2012 Full Fat RR 4.4 TDV8 (now gone)
2006 VW Touareg 3.0 TDi V6

It's never going to cause a runaway as it's not dumping oil in the intake side. Mine smoked very badly when I first had it but I only get a mild puff now and again when I use the 2nd turbo. Seems to be worse in summer as I've gone a few months in the winter without using the 2nd turbo and not seen smoke. 2012 TDV8 Vogue (L322)

Thanks for the replies. Just changed the oil again after draining the mini sump. Made sure the engine was nice and warm and no smoke at the moment.
Oil gauge is one graduation below maximum [hot] so I'll keep checking to see if it's using any.
Interesting that while the engine oil was draining I went to clean all the usual crap off the MAP sensor only to find it was sparklingly clean!! Never been like that before.

Result
I'd think very carefully about that turbo drain mod. Tapping into sumps is not something to be taken lightly IMHO
I know of an "ex-smoker" 4.4 TDV8 that now does not smoke as the driver boots its regularly when warm. Also undertakes 6 monthly oil changes etc. Gone to a good home: 2011 4.4 TDV8 Vogue SE Buckingham Blue with Ivory and clear glass = "Rory"
2025MY Defender D350 90 in Silicon Silver on coils
1974 Series 3 Lightweight = "Millie"
Many, many other Landies over the years
My preferred specialist: www.glenrands.co.uk
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