Trad Girl might be interested in this reel, as I think Cathal McConnell might have been first to record it, and he has it as a Co. Fermanagh reel. Frankie Kennedy also had it as part of a solo on an "Altan" recording, I seem to remember.
‘Big John’ is fiddler John McManus of Fermanagh, a friend of Cathal McConnell’s. He appears on Cathal’s album, ‘Long Expectant Comes at Last’ - and also on the recently released ‘Hidden Fermanagh’ CD.
Here’s another lovely reel named after John McManus: https://thesession.org/tunes/5950