You have to remove the trim above the glove box, then remove the whole glove box unit (about 8-10 screws) and you will find a rectangular plastic cover in which you can gain access to the pollen filter.
No wonder I got charged £300 for the 1yr/12000mls if they make them that awkward to service.
I think you will find it is part of the 18000mls service.
According to my 36k service bill, the pollen filter only contributed about £25 to the overall £377 cost. The odd thing though I've just noticed on the second page of the bill it says pollen filter out of stock! so begs the question if it's been done?
