@ OP, There's jobs where you actually have quite some "free time", which isn't really free as you have to be at the office rather than wherever else you wanted to be, expecially jobs that require availability, so you're basically sitting waiting for calls to come in.
But it seems like you know your ****, you can single handedly solve UK economy issues it would seem. The **** are you doing on here then. I'm sure your services would be payed for properly.