Short little discussion question but:
Most timelines that involve longer versions of the American Civil War tend to have the conflict dissolve into guerrilla warfare in 1865, if not earlier. This is understandable considering that Porter Alexander suggested this to Lee at Appomattox and the considerable portion of the war, away from the major armies that was a bushwhacking conflict, and the use and threat of use of paramilitary violence during Reconstruction by redeemers.
In contrast to this though, I'm interested in hearing discussions about how long the war can go on, with any divergence following the founding of the Confederacy, while maintaining a reasonable degree of control by the Confederate government while still being defeated? Is it only a matter of months past April, 1865? A year? Two? All the way to 1868?
And I'll note I'm not asking if the Confederacy can win. Just what the longest potentiality is, and how that could come about?