It's possible. You have to ask for a instant uppgrade on points. It takes 10 000 points for every level of uppgrade. So if you have booked a Business class room, you would have to pay 10 000 for a Junior suite, and 20 000 for a higher class suite. The amount should correspond to a per night rate. But you could be lucky aswell. I asked for a uppgrade in Lucerne last weekend. Even though i stayed two night they only withdrawed 10 000 points! Could be that the elite status helped me out.