You can use a specific calendar for spreading posts across the Interwebs. Add '#fbpages' (or change the hashtag below) to each event's TITLE that you want to go to your Facebook Page. In the DESCRIPTION field of the event, put the message you'd like posted on your page. With a troop of similar Applets, Google Calendar can be your HQ for scheduling posts to Twitter, Tumblr, and Facebook!
If
Event from search starts
This Trigger fires a set number of minutes before the starting time of an event on your Calendar that contains a specific keyword or phrase in the event’s Title, Description, or Location. Ingredient will be based on the zone set in Google.
Then
Create a status message
This Action will create a new plain text status message on your Facebook Page.
Explore more great ways to automate Google Calendar and Facebook Pages