I do not understand why Tiller, then a 2nd Lieutenant would be applying for a commission as a Cadet.

He was at the time receiving $90 a month while a 2nd Lieutenant. A 2nd Lieutenant's pay was at the time $80, but could
receive an extra $10 if serving also as an Adjutant. I do not see such evidence in his record.Com

Perhaps he was looking for a Cadet commission in the Regular Army as the requirement for a Lieutenant's commission in the old army required one to be no younger than 20. See Custom's of the Service Art. 570, p. 189.

Equally puzzling is the fact that Cadets were paid half that of a 2nd Lieutenant. Perhaps a commission as a 2nd Lieutenant in the P. A. C. A. was not considered a permanent rank and one could hold that position while his permanent rank was that of a Cadet. Witness the number of officers in the Federal Army had to revert back to their permanent ranks post War, Custer for one. We saw the same situation in WWII.

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William T. Tiller, Orderly Sergeant, Captain Hart’s Artillery Company, enlisted June 21, 1862 at Little Rock by Capt. Hart for the war, formerly Corporal Hart’s Battery, November 12, 1861 to June 21, 1862, paid 2nd Lieut. W. T. Tiller, February 3, 1864, $90 for the month of January, 1864, Lieut. W. T. Tiller will report to the Marine Dept. at Houston as Ordnance Officer February 4, 1864

M317: Compiled Service Records of Confederate Soldiers Who Served in Organizations from the State of Arkansa