Since we don't participate in any of the programmes we have to pay cash (about 4800 Euros for 4 nights) and an upgrade seems unlikely
As alternative accomodation we have an offer for an awesome 60 sqm appertement located directly at Campo San Maurizio for about 850 Euros for 4 nights (
www.domusvenetia.it) - maybe we will try this one and spend the remaining money for fine dining at some Michelin rated restaurants