West Yorkshire's habit of using 'while' to mean 'until' is confusing...
Funnily enough, two colleagues from Yorkshire (I was also born in Leeds) just did that in a meeting of my London-based employer:
"How long is it since you've been in Yorkshire?"
(meaning, "For how long have you been basing yourself there for home working?" as opposed to the usual meaning). But none of the southerners present seemed to notice. I might not have done either, but for this thread.