From other clues in the text, I think this recollection dates to the period 1815-1819.

Quote

Hilsea Barracks are an extensive set of cottage buildings, situated at a distance of three miles from Portsmouth. After our arrival there, an order from the Horse-guards appeared, directing the officers of all regiments to practise the broad-sword exercise: this was considered very annoying by many, and some went so far as to pronounce it perfectly ridiculous, since in all their experience they had never known an instance in which the knowledge of it would have been of any service to an infantry officer in action. […] An additional annoyance was derived from the fact, that a place was constantly assigned to me in the awkward squad; though an older officer, and an older man than I, was raised to the first squad.

Ross Lewin, Major (1834) The Life of a Soldier. Richard Bentley, London. source

Interesting use of “awkward squad” there.