"The Day I Spent With Mick" is a Cuz Teahan composition that caught my eye in his tunebook because it leaned heavily into the quick B / C# alternation that's very natural on a button accordion with a D row. The only recording I'm aware of is on Niamh Ní Charra's fantastic tribute album "Cuz”, I use one of her tasty little variations the last time through the A part.