test pressing/white label

I wonder if you can help with this one?!

I won a disc in the queen raffle at the O.I.Q.F.C
southport convention - 1991
It is a 12" vinyl of I'm going Slightly Mad.

There is nothing printed anywhere...only a hand
written message in the corner of the white sleeve,
reading: '11.2.91, 12 queen 17 a/b - JW'
and the same JW initials on the plain white disc label.

I'm only guessing at JW...it could also be 9W or 2W or something else?!

I've kept hold of this since i won it in 1991, but don't know anything about it

So if anyone has any details at all, that would be
fantastic! Many thanks, Glyn

Test pressing is probably the best description, given the accuracy of the of the catalogue number.

JW could be the cutting engineer, or could be some sort of in-house code - the quality and colour of the vinyl.

Value is tricky - this is (presumably) so close to release that it's unlikely to have any unique material, but may still be of interest to some of the more obsessive collectors. I wouldn't expect you to get much more than £25-30 for it, but others may well differ.