Tonight I found out the expensive way that there's a sneaky rule that Uber has applied to the set destinations. If you do add an arrival time after doing one trip without an arrival time set, Uber will rob you of the second 'set destination' token. If I knew this there's no way in hell I would have added an arrival time. For me it meant that I had to drive home 30km without any trips. Might not seem that bad but it's a public holiday and I would rather not waste an hour of my life because Uber wasn't upfront about their system.