Legal Question in Employment Law in California

Your facts aren't exactly clear. If she has fully resigned but agreed to come back occasionally for work on an ad hoc basis sometime in the future, she is entitled to vacation pay payout. If you keep her on your books as an employee for your convenience of not having to do the new hire paperwork and bookkeeping when she comes back, that does not absolve you of the duty to make the pay-out. On the other hand, if this is just a transition, and she moved from full to part-time work that is currently scheduled and ongoing, that might require a different result. Ultimately, however, if push comes to shove she has the right to fully quit and collect the pay-out and you would then have to decide if you then still want to bring her back part time and on call. So this is probably not one you can win at the Labor Commission were it to go that far.