Last minute award availability?

I'm looking to travel to San Francisco between Christmas and New Year (ideally on an award ticket!), does anyone know if VS typically release economy award seats nearer the time of travel like the US carriers often do?

I've got my fingers crossed although I can't say I'm too hopeful! Is there a way of seeing how full the flights are in Y on these dates?

Thank you!!

Reward seats can and do appear at any time. You just need to keep checking, daily if possible. Most V-Flyers will attest that if you're patient and persistent, you've a decent chance. Having said that there's no guarantee, and you're looking at a popular route at a very busy time of year. But if you're a bit flexible with your dates, you may well strike lucky.

Expertflyer.com is your friend for load checks (though you need a subscription).