Help wanted.

[sharpiefan]

I've got a query. I know I read in an AoS novel about the captain taking six more Marines and a Sergeant on board, from the Chatham division, who were later identified as taking part in planning a mutiny. The guy reporting it to the captain notes that the speaker he overheard was one of the Chatham marines because he was wearing 'the badge on the sleeve that they wear'.

I know it's not from the Aubreyad, Drinkwater or Bolitho books.

I can't remember if its from one of the later Kydd novel or one of the Peter Smalley HMS Expedient books, and was wondering if one of you could help me narrow it down?