After reading over this article, it looks like only one order of battle is attempting to represent the entire Siege of Petersburg. This is a mistake due to the nine month length of the siege. The Army of the James was initially composed of the X Corps and the XVIII Corps, but on December 3, 1864, all of the White troops were placed in the XXIV Corps and all of the Black troops were placed in the XXV Corps. This order of battle has all four corps as if they were separate entities throughout the entire Siege.

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