ok so checked in with BMW this morning and two things stand out to me.
The description of part 11227561765 is 'Flywheel' and it costs Ł233.34 from BMW, the dealer print out shows the description as 'Flywheel/Twin Mass Flywheel'
I therefore do suspect that my car does NOT have a dual mass flywheel, the price is way cheaper than a dual mass flywheel would be and i suspect they use a generic title and picture for the flywheel.
Going to ask for a photo of my flywheel since it will be exposed anyhow, but i suspect i have a single mas flywheel. The chap at BMW (different branch) said they haven't sold any of these, but they do for the cooper S.