Marshalling is volunteer work and unpaid. The track location is valid and seeing as Thruxton run very few track days you will be ltd, Combe is an alternative though, trouble is, if you get your license, you are under probation for a year where you must get 6 stamps (most likely unpaid) you will be at the bottom of the list and if you do get a call, no matter where, you will need to go or forget getting that call again.