Last night I updated to Logos 7 basic from Logos 6 Starter Library. I added a couple of reading plans on the Mac app and made sure to sync. I went to my iPad Air 2 which is on iOS 10.2.1 and Logos 5.11.20186. I tried to sync, but nothing happened. I tried to sign out of the app to see if I could sync, sadly there is no sign out option, so I had to delete the app. Deleting and signing into the app allowed the documents to finally come through. However, I had to do this whole process after I made a small change to the reading plan On my Mac app.
Please let let me know if you have any questions or if sync is something I have to pay for.