Have you read this thread?
http://www.jampot.com/forum/viewtopic.php?f=8&t=11470
You need to be a paying member to see the link, however I can tell you the recipe for polychromatic blue isn't listed in any source at the club's site,
the one for polychromatic red is listed though.
One of the links points to this document:
http://archives.jampot.dk/technical/Tank_details_and_transfers/AMC_Paint_codes.pdf
Maybe you need to contact Anthony Curzon (aka John Donne) about this. He is a frequent contributor in the AJS/M O.C forum. I haven't seen him on this site.
See also
http://www.jampot.com/forum/viewtopic.php?f=12&t=6538
There is also a booklet available from the club which list paint codes. I couldn't find it in the shop listing, so you may have to be a member to obtain a copy. No guarantee that it contains the information you are looking for. Maybe another AMOC member will chime in ....
Regards,
Knut