Hi Rod,
My readings of the earlier (ie central European) structure was that the units operated much like Prussian battalions of the same period, having been trained by "rogue" Prussian officers, in four companies/eight half-companies and using the third rank as schutzen, or skirmishers. Have you come across anything that indicates that the regiment in British service shifted immediately from three ranks to two? (It would be one thing to shift their rank/command structure from Prussian to British, but their training and tactical stance when in the field?) If they did alter to two ranks, what was the physical position of the remaining "jager" still attached to the nine companies that formed the main body of the regiment in the Peninsula? Could the main unit have done what many of the larger British regiments did in the Peninsula, and formed an ad hoc "internal" light company to compensate for the absence of their dedicated/detached skirmishers?
Brendan