GoDaddy tells us:
We'll be performing maintenance on your server between February 27, 2018 and February 28, 2018 MST.
We're installing patches on your MAMainNew server to stay ahead of potential security vulnerabilities. Between Tuesday, February 27, 2018 08:30 PM and Wednesday, February 28, 2018 08:30 PM MST, you may experience up to 30 minutes of intermittent interruption to your hosting services while we install the patches.
After the patches are installed, we'll reboot the server and you'll be up and running.
So basically anytime in that 24 hour period there will be a 30 min outage for patching.