Right now San Francisco – Singapore non-stop has amazing award availability as well. There are numerous dates where there are 8 award seats available, when booking into the future. In fact there are days where both of Singapore’s daily A350-900 San Francisco non-stops have 8 award seats available.
Singapore Airlines does a very nice job making premium cabin award seats available to its own members, often close to departure but almost certainly booked far into the future. The best availability for non-stop awards to Singapore from San Francisco is September – November right now.