In my research on my "Abel" ancestors I had had similar experience with the multiple spelling of the name "Abel".The earliest "Abel" ancestor that I can trace to is James Abel who was born in Abbeville County, South Carolinan in 1797.All of "Abel" folks in that county & in that census are listed as "Abel".I have a Joseph Abel who served in the Stevenson Creek (Abbeville Co. South Carolina Loyalist Militia in 1780 & 1781 & a John Abel who served in the Long Cane Creek (Abbeville Co.) Loyalist Militia in 1780.I feel that I am descended from one of those two Abel folks but have no proof.
I have a copy of a general affadavitregarding service in the Indian Wars from a William C. Abel of Attalla County, MS, dated 1888.In the affadavit, William states, "My name is Abel not Abels, though the people around here generally call me Abels and the party in filling out my previous affadavits wrote Abels"
I have a transcribed copy of a letter from a John Jackson Abel to his brother Elijah Abel dated March 1st 1873.It shows that William Abel was born July 1, 1781.He had a daughter named Sarrah, b. 1800 and a son Joseph b. 1801.I don't know if this folds into your liine or not but I don't believe it folds into mine diredt line.Undoubtedly, all of the Abel fols who came from Abbeville area of SC were related in some way, regardless of how they spelled their names.