How does destination filter work? You only get 2 a day?
You get two destinations a day. If you set it, but don't do any rides, it doesn't count.
If you set it and do three back to back rides towards your destination, it only counts as one useage. Basically, it counts once you go offline after completing a trip (or trips) toward your destination.
You get a fresh new set of two destinations at midnight. No roll over though.