Yes, you’re right, it is used in East Tennessee.
From what I have heard the East Tennessee accent is in a class by itself. they say ‘bewk’ for book, in other words pronouncing ‘book’ to rhyme with ‘boo’. East Tennesseans do sound a bit like Lowland Scots, or the ‘Lallands’ dialect.
A beautiful style of speech BTW.
So beautiful my family married into it! My sister married a great guy from there first and then I met my wife in Knoxville after college. South Carolina and East Tennessee seem to be good fits for each other. :)