Question : How many days should you spend in San Jose if you're flying in from Warsaw?
Answer : Of course you're not most people, but if you were, you'd stay roughly 10 days.
Question : Is price more important than specific travel days for you?
Answer : Sunday is your cheapest day to fly in February. Having flexibility in your travel plans means you can save, so be sure to plan ahead when possible.
Question : How often are prices changing for this route?
Answer : Prices for this trip tend to change much more than others. The further out you book a route, the more likely you are to save.