Does the Octavia estate VRS blackline (2012) arm rest have an MDI connection point for an ipod

Nope it didn't come with MDI. And it'd be in the glovebox any way from memory.

Quite easy to retrofit apparently

As far as I can recall from the manual, fitting MDI takes the place of the normal aux in on the back of the head unit. So you can't use both.

Might I suggest a bluetooth retrofit? BT to my iPhone works awesomely well in my Elegance.

the Amundsen+ in the Blackline already has BlueTooth capability - and an aux socket on the front of the unit. and space for an SD card

You can have AUX-in and MDi

if the car has Aux-in it is connected to the back of the radio, when you Retrofit an MDI the Aux-in is wired into the MDI plug

You can have AUX-in and MDi

if the car has Aux-in it is connected to the back of the radio, when you Retrofit an MDI the Aux-in is wired into the MDI plug

I believe there is a different mdi loom depending on if aux in is present or not

I believe there is a different mdi loom depending on if aux in is present or not

my car came with just the Aux-in

I have retrofitted the MDI and changed the existing aux-in wiring.

Both work fine