the instructors don't like it too much if you duck out, worried about their tip at the end of the week. Which I can't blame them when you find out how much they are paid by Ulen.
I'm in Bansko now and my ski lessons witht he Ulen school is 10 til 12, 1 hr lunch then 1 til 3.
Got seven people (inc. 9 year old) in with ski school - all fine by me....just limited pistes due to lack of snow.
...but at least still ski-ing.