Unfortunately I'm not a UK resident either. I've applied for the US card - I doubt I'll be approved but there's nothing to lose.

I have another newbie question. The corporate rate I'd be using is cheaper than the regular weekday rate, but more expensive than the regular weekend rate. Is it possible to book weekends at the weekend rate, and weekdays at the corporate rate? (if necessary all the stays could be booked independently, but would be consecutive).