Doublewhite lines

I have just picked up a fixed-penalty notice for overtaking whilst crossing double-white lines. The offence occurred whilst overtaking on a country single-carriageway A-road (60mph limit in force) in good weather conditions in daylight and with no other traffic in sight (the "bobby" was hiding!!). On the road ahead I saw, what I thought, was a pair of hashed lines along the centre of the carriageway, with diagonal hash marking between the lines. In other words, I thought I was OK to overtake in the conditions.

I was later pulled over by a motorcycle policeman and told I had overtaken on double-white lines - he issued a fixed-penalty notice to me. I later went back to the scene - sure enough they ARE solid lines, but have cats'-eyes embedded in each of the white lines, each eye is level equidistant with it's neighbour on the other line. Thus, to me, the lines could easily be interpreted as being dashed - they certainly appear similar to the example picture in the Highway Code. Ordinarily I would expect double-white lines to have a line of cats's-eyes in the space BETWEEN the solid lines. At night time I suspect that these relectors could convey a false impression of the actual road marking layout - just my opinion though.

Do I have a valid argument for arguing this one in court?

I'm not trying to weasel out of paying up, it is simply that my pride is hurt because I'd never consider consciously committing this kind of breach.

Thanks.