LNR, like many operators, often relies on overtime to run services particularly at the margins but even during the middle of the day (to cover for sickness, holidays, etc). For someone to come in when they're not rostered or to stay later than they're contracted relies on firstly their desire to earn a bit more but also their goodwill. Right now LNR are in the midst of an industrial dispute with a big chunk of their staff which means that the staff probably aren't feeling a whole hell of a lot of goodwill towards their employer. So when they get the phone call asking "any chance you can come in and work xyz today for me?" the answer is far more likely to be "nah, thanks anyway!". The results are then fairly predictable...
At least that would be my guess!
