Apparently the British Army may have been slightly different. The following info is as was related to me during a lecture on "Field Organization and Command" by the "British Brigade" at a recent garrison weekend at Old Fort Niagara. I cannot give you source material to reference.
The terms "Regiment" and "Company" were houskeeping or organizational in nature and were not used in the field. In the field command and movement was by "Battalion" and "Subdivision" (subdivisions were of course smaller units within a batallion--they could be called "platoons" or "squads" but varied in size and makeup.) For instance the Regiment consisited of 10 companies (8 regular or "hat companies" on grenadier company and one light infantry company). Often, field commanders would take, grenadier companies from several regiments and form a batallion of grenadiers, light infantry could be used in the same way. The remaining "hat men" of the various regiments could be formed into batallions and subdivisions as needed.
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