Facebook has made another change (shocker!), and I first saw it on my "Tawny" Facebook page. It looked as if there was no option to schedule posts any longer while on a computer (no problems so far on Android mobile app).
Turns out, you actually CAN still schedule posts, it's just a little tricky to figure out how. It was hidden in plain sight for me! I have photos below!
First, click "Post Options" right under where it says News feed.
Next, click "Now," right beside the "Share" button under "News Feed!"
Now you're ready to schedule away!