Here’s some info from the Official Records which may be of use.

OFFICIAL RECORDS: Series 2, vol 8, Part 1 (Prisoners of War)
PRISONERS OF WAR AND STATE, ETC.

HEADQUARTERS DEPARTMENT OF MISSISSIPPI,
Vicksburg, May 11, 1865.

Major General E. R. S. CANBY, Mobile, Ala.:

Your dispatch of the 9th via Meridian is receiving. All the prisoners from Ship Island had previously been turned over to the Confederate agent of exchange, on parole in lieu of prisoners delivered by him.

I am, sir, very respectfully,

N. J. T. DANA,
Major-General.
Page 551

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HDQRS. ARMY AND DIVISION OF WEST MISSISSIPPI,
Mobile, Ala., May 11, 1865.

Brigadier General T. KILBY SMITH,

Commanding District of South Alabama, Fort Gaines, Ala.:

SIR: The major-general commanding directs that all officers and men now held as prisoners of war within the limits of your command be released on special parole, in accordance with the stipulations of the surrender of Lieutenant General Richard Taylor and his army. All paroled prisoners are at liberty to return to their homes, except General Cockrell, and such others as belong to loyal States (including Kentucky and Missouri), who are required to remain within the lines of the military division until the pleasure of the War Department in regard to them has been communicated. Forms of blanks are transmitted, herewith inclosed.

Very respectfully, your obedient servant,

C. T. CHRISTENSEN,
Lieutenant-Colonel and Assistant Adjutant-General.
Page 552

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HEADQURTERS DEPARTMENT OF MISSISSIPPI,

Vicksburg, Miss., May 14, 1865.

Brigadier General G. L. ANDREWS,
Provost-Marshal-General, Meridian:
(Care Brigadier-General Tucker, C. S. Army, Jackson.)

The officers and men sent here from Ship Island were understood to be as an offset for the men delivered to us on parole by the Confederates, the Confederate commissioner of exchange having received official notice from General Grant, and it is also undersood from General Canby, that any men in our hands due them should be delivered here. They were all paroled on the rolls in these words:

The officer signing this parole does so in behalf of all the men above his signature, and all described on this roll are not to perform any military or constabulary duty until regularly exchanged.

It was agreed that these men could return to their homes and that they should not be distrubed so long as they obeyed the local laws and observed their parole. The papers they have are furloughs, given them by Colonel Watts, agent of exchange, C. S. Army.

Full rolls are in the hands of Captain Sterling. The Confederate agents of exchange also have a copy, and another is retained here.

Very respectfully,

N. J. T. DANA,
Major-General.
Page 556