What does irk me though (for the FR guys) if I have understood correctly is that you have to travel in your own time to start a series of duties which is at a base other than your "on paper" home base, is that correct ? Then surely that is simply a duty requirement at the behest of your employer (whoever that may be) which therefore invalidates said day off as a day off for the purposes of ensuring adequate legal days off are provided ? I apologise if I have misinterpreted and this last paragraph is incorrect.
All correct.