Click the Add-ons Menu > Postamatic > Publish Posts
The tool will then loop through all the posts in the sheet and upload to Google any of the posts with Today's date in Column A and that does not have 'uploaded' in Column S already.
Postamatic supports automated daily posting. This incredibly useful feature allows you to set up a number of posts in the future. Then each day, the tool runs at an hour window of your choosing, and will post to GMB the posts with dates that match the current day's date.
Here's how to set it up.