Hah! I guess some people are just crazy and can't do without their job. I mean, I could respect that if your job is the best thing since sliced bread (like being a gay fluffer or something), but apart from being a pilot I don't see too many earth-shatteringly fun careers at BA.
The unpaid leave thing, though, I'd be down with. Most people who're fairly settled can do a month without income with relative ease, so why not take the additional holiday? Dang, I'd sign for that stuff right here and now if I could (but then, I don't have many expenses these days).
One thing's for sure: I'd spend one day of that month going to work to see who came in for no pay. And laugh, laugh, laugh.