We went through this a couple of months ago and Timothy Denyer (FCL,Gatwick) ruled that a multi-leg x/country was only one supervised flight for the purpose of removing the restriction.
I agree with the remarks about being paid for supervised flights. Although I am not in the aircraft, I have to be instantly available should the need arise and so I should not be doing anything else during the solo flight. Sadly that is no longer the case where I teach.
It seems that either the student pays dual for student solo flights or he/she pays solo and the instructor doesn't get anything. Ho hum.