To see what you have scheduled and make the changes, you need to proceed to activity log by going through admin panel at the top of pages. If you can’t see the admin panel then click on red admin panel button in upper right corner. After that, choose edit page and activity log. With this, you will see schedule a Facebook post. If you want to edit the scheduled post then you can only change the time. To edit the text, you can cancel the post and redo the scheduling process. To smoothly change or change the time, mouse over your upper-right corner of post in the activity log.