Copy the firmware update file onto the thumb drive, and then remove it from your computer.
I've customized my tablet and removed a lot of the unnecessary Amazon apps.
I really like how my Amazon Fire HD 10 looks right now and don't want to see it get messed up because of an update.
Since it is rooted, use ES File Explorer (change settings to give it root permission and show hidden files) and rename the file /system/etc/security/ While you are at it, I need a copy of the file if you don't mind.
I am trying to restore mine and lost it during a factory restore.
The time it takes to install the firmware update on your Sharp Aquos TV depends on the size of the update and the speed of your Internet connection.