Hi Clay!
That signage is correct, but 56 is technically not tolled. The next tolls are IF you get off at Orchard or 31, or if you don't exit, MM 61 (https://www.illinoistollway.com/travel-information/maps click on "toll rates by plaza" for the icons to show). 56 is not tolled heading west. I suppose we could say 'tolled' from galena to 88 as there's no way to escape the toll after passing Galena.