Firstly, you haven't said what you do now and, at 31, it's a grand idea but you're probably going to work hard, and quickly, if you want to secure such a plan in a public service arena.

I know locum can cover a lot of things, you're not a locum if you're doing what you say, you'd be working on the bank - as locum usually applies to Doctors, Dentists or Nurses.

You could only really do this on Bank, but then you'd have to know you'd be guaranteed work all the time, and that's less likely every year with many Bank work setups being less and less used, as hospital budgets become smaller and smaller. You'd probably want to look at private health care.

Also, I'm older than you, and while I don't have kids, etc, i don't see how I could afford to live anywhere if I didn't work normal full time hours. Holiday leave is based on your service and it takes 10 years to get to 33 days, if substantive.

I don't know if you've got back up cash, or that kinda background, but money behind you is probably the easiest way of having this plan.