As it says, all four corners dropping overnight but not down to the bumpstops.
Disconnected the battery and no drop. So I think I don't have a leak.
Reading the manual, I think its dropping due to the wake up and relevelling procedure. Its making adjustments downwards as it cant get the car level.
I did notice that while doing a guided calibration a while ago that the movement of one of the rear corners was a bit jerky and I struggled to get it level using the GAP tool.
My conclusion is that I have a problem with the rear valve block.
I have ordered an O ring kit, will refurbish and see if this solves it

Am I on the right track? All the best
Chris

Others;
1966 Jaguar 3.4 S type
1992 Jaguar Xjs 4.0 Coupe
2003 Jaguar Xjr

It 's more likley to be a faulty height sensor giving a false reading to the ECU which keeps dropping the car in an attempt to level it as you say. I think if you have disconnected the battery and it doesn't drop this indicates this even more. 2012 TDV8 Vogue (L322)

Thanks,

Is there a method or way I can identify a dodgy level sensor? All the best
Chris

Others;
1966 Jaguar 3.4 S type
1992 Jaguar Xjs 4.0 Coupe
2003 Jaguar Xjr

As you had a problematic calibration procedure with one of the rears this would be the best indication it's faulty. There are patern part sensors available but most people go for OE to ensure trouble free operation. 2012 TDV8 Vogue (L322)