V50 Electrics : Active Bending Lights - How to change bulb?

[JInge]

I have a 2011 V50 Drive with xenon ABL lights, and the low beam has failed on one side. I'd like to be able to replace the bulb myself, but I'm stumped as to how to remove the bulb from its holder.

I can remove the light assembly itself and access the bulb with no problems, but I can't see how to take it out. Videos I've found online for other models either show retaining clips around the square base of the bulb, or a clip around the neck of the bulb with tabs that you rotate to release it. I can't see either of these on my model. Instead it looks like it is inserted directly into an octagonal part at the back of the projector unit, and it doesn't seem to want to move if I pull or twist it. The answer may just be "pull or twist harder", but I thought I'd ask before I broke something!

The bulb is an Osram Xenarc D1S, and the part number of the headlight unit looks like it is 31299600. Any pointers would be gratefully received!