(The drop down list, of course contains two more years: 3909 and 3910.)
I don't think it is year 3908 according to some non-Gregorian calendar, unless they're also one day-of-the-week behind for some reason. It simply means that all hotels in Prague are full till Kingdom come, although there might be limited vacancy for the week before.*Not going there anytime soon. I was window shopping for a vacation. Is that so bad?