Talk:Characters/@comment-183.87.140.130-20160419162913/@comment-26249703-20160419172137

Theorised that it's a comination of the latter two. You'll get them eventually, even without opening the app, but racing a lot will make them appear quicker, anywhere between 48 hours to 24 hours, respectively. If you race signed in and signed out, that can also have an impact (I've had two free agents within a few hours).