First and foremost, performing Factory Data Reset from Settings/Storage & Reset, followed by 2 complete power cycles will be useful
If your update results in a boot-loop and your home screen fails to appear, follow the steps at this link https://www.reddit.com/r/AndroidTV/comments/8tr6cl/mdz16ab_oreo_cant_wait_link/ Be sure to follow the bolded section
If you have an AVR in your setup and are getting black screen after update, disconnect all your devices from power source for 5-10 minutes and try again. This will serve to reset the HDMI connections.
This is a compilation of effective hints found circulating the interwebs.
Nice write up. Thank you.