Looking to update maps on 2009 A8.

[legacy4cam]

As per title, I have a 2009 A8 which, unless I'm mistaken , has the hard drive (HDD?) navigation.

I'd like some more recent maps , but am getting confused with talk of updating MMI operating systems etc..Is this necessary?
To my knowledge everything currently works as it should.

What do I need to do, is it a part of the 3 disc MMI update discs I read about here, or is it more simple if I just want more up to date maps?

Thanks in advance,

Iain