I don't see the purpose in this feature even if your alarm was at 4:00. Why wouldn't you keep charging until the user picked his phone off the charger?
One thing you might do is only charge to 80% or 90%, to improve battery lifetime, unless you detected the user is going on a long flight tomorrow and needs it at 100%. But I don't see any reason for the opposite behaviour.
One thing you might do is only charge to 80% or 90%, to improve battery lifetime, unless you detected the user is going on a long flight tomorrow and needs it at 100%. But I don't see any reason for the opposite behaviour.