I'm strongly thinking it is this, oil oozes out if i poke and prod it and its directly above where I observed those freshly forming drips.

there no reason the seal should be leaking unless you disturbed it I think its running down from the pump

Can I ask you to watch this short 1min video I recorded, I believe it comes from above and drips down onto the pump, and onto the little stubby item next to the pump. The only thing above is that shaft and the filter, and the filer is dry.

https://www.youtube.com/watch?v=TKnjYigo2vk

That's quite a leak!
So it doesn't need the car to be moving, just the Haldex to be pressurised?
You changed the filter some time ago in situ?
Are you absolutely sure that the filter cover is dry at the base?
Changing the filter in situ is not that easy IMO (but you do have the smaller flange) and I understand that the cover o ring being nipped when being replaced is a common issue.
That said, I would have thought that it would have manifested early-on.

So you didnt disturb the drive flange in any way but you did replace the filter and took the pump out.

To my mind if its not the pump, its got to be the filter.

I took my haldex off to service it as doing it in situ seemed very awkward. Jules

Hi both, yes I took the filter out with the Haldex in situ (it was a pain because the hook on the filter broke, but I did manage to change it). Just a few days ago I took the cap off as the set you directed me to had another filter, but I got as far as taking the cap off then stopped, but the cap was totally oil free. Could I have done something really daft like put filter in wrong way? Or perhaps it’s totally unrelated to my work back in November. I did notice more oil dripping even after driving without the Haldex fuse after a couple of days, I expected any remaining oil was just sit at the bottom because gravity. It’s lost all 700mil or so now since Sunday, it’s gotten worse.

Have you got a mirror on a stick to get a closer look at the source - that amount of leak should be obvious if you can get it in sight. Jules

Hi, I am going back to the seal I pointed out before, it does not appear to sit flush and it looks a little degraded. I don’t think I can take the full haldex off diy so I’ll get it to some local experts and see if they concur and hopefully get her running fully again.

That's not the seal that you are looking at there. The black plastic is an extension of the flange and rotates with it. I assume that its function is to provide physical protection to the seal that sits within the Haldex housing.
It is of course still possible that the actual seal is faulty though.