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!
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