On Martin Carthy's 1968 album But Two Came By I was surprised to hear him sing the opening lines of "The White Hare" as:

Near Howden town, near Howden town, as I have heard them say
There once was a white hare that used there for to dwell

Where I would have expected the first line to end in "tell", as I recall Joseph Taylor's and also The Watersons' version does. I put it down to a natural change, mistake whatever. The two tracks later on "Poor Murdered Woman" he sings the opening lines as:

It was Yankie(?) the Squire as I've heard them tell
He went out a hunting all on one fine day

where I'd have expected "say" instead of "tell". Strange that there are two changed oddities on one LP, which somehow complement each other.