Upgrades on Virgin America with VS miles?

Hi All,
Sorry if it has been dealt with, (did a search and couldn't find the answer) but... what are the chances/rules for getting upgrades on Virgin America using VS miles, on a revenue ticket? Is it possible, or unlikely?
I'm thinking of 'main cabin select' to First for an NYC to SFO flight. Work is buying the 'Select' ticket, I'd like to use my own miles to get up to First, if I can.
Thanks!
Sorry if it has been dealt with, (did a search and couldn't find the answer) but... what are the chances/rules for getting upgrades on Virgin America using VS miles, on a revenue ticket? Is it possible, or unlikely?
I'm thinking of 'main cabin select' to First for an NYC to SFO flight. Work is buying the 'Select' ticket, I'd like to use my own miles to get up to First, if I can.
Thanks!