Resignation & incentive bonus payouts

I've seen a couple other topics addressing this but nothing that quite answers my specific situation. I work for a company in CA that does not have an employment contract per se, but does have a document outlining bonus payouts. Document states that you must be employed through the end of the incentive period in order to be eligible, but does not state you need to be employed at the time the bonuses are paid out, typically late February/early March. I planned on tendering my resignation now with a leave date at the end of March, as it is a position I feel needs a good deal of time to fill and train. With that said, can my company legally ask me to leave prior to March in order to avoid paying out the bonus, or are they obligated to pay it since I worked through the end of incentive period and am willing/able to stay until bonuses are paid out? Any insights would be greatly appreciated!