This question is a wee bit up in the air, but I am curious. My maternal grandfather, was from Monaghan, Ireland. He was a Protestant, but beyond that not much more is known about him. Monaghan is in Ulster but wasn't a prime area of Presbyterian settlement. On a DNA test I did Igot nothing to do with Ireland, but a substantial amount of Scottish. In this context, I did a test with LivingDNA. They are notoriously reliable for their 'British' regions. Literally 25% of my ancestry was derived from what they have as the 'SW Scotland & Northern Ireland' cluster, which is synymous with those in Northern Ireland who are of Protestant Scottish origin and is distinguished from those who are Irish. Now, McCabe is often written of as both an Irish and Scottish surname, but in other sources, it appears that is now an exclusively Irish surname, although it was brought over from Scotland in the late Middle Ages. In this case, whilst there are plenty of McCabe's in Scotland, one wonders whether they are all of Irish origin.
What I want to ask is, are they are of you in the Ayrshire area with the name McCabe, and not of Irish origin?