I would recommend not to upgrade. There is still battery life issues, subpar camera quality compared to 8.1 and on top of that enjoy the message you charging your phone slowly error message despite using ms official charger.
If upgrade advisor doesn't update the work around is going from insider preview select third ring then opt out. You will then be on latest stable release along with the above issues I highlighted. That's why I went to back to 8.1 and said hello again to two days without charging my phone