Xenon bulb holder removal

[SBK740]

I need to change my LHS (RHD vehicle) factory Xenon lowbeam globe. I've got the new globe but cannot remove the old one. When I remove the backing of the light, and remove the connector, there is a brass coloured item which looks to be a holder that seems fixed to the lens. This contains the globe.

I tried turning both anti-clockwise and clockwise to no avail, does it need to be unscrewed or is there a notch I am missing?

Thanks.

http://blog.bavauto.com/9059/bmw-e39-5-series-hid-xenon-bulb-replacement-528i-540i/

Showed how to do it.