iOS 11.1.1 'Install Now' grayed out

iPhone 8 plus:

iOS 11.1.1 available, but 'Install Now' is grayed out with message, 'You can install this update when your iPhone is finished restoring from the iCloud backup'.

1. I've had the phone for over a week

2. iCloud restore was finished within the first 30 mins I got the phone

3. It's been plugged in overnight, every night

4. it's always connected to Wi-Fi when attempting an iOS upgrade

Anyone have any clues?