We had a 830 ressie and checked in early and were seated right away. We just missed rope drop and had a 5-10 minute wait on the Safari ride (basically the time it took you to walk back to where you get on the jeep).
If you want any chance, be sure to take care of your check early on in your meal. That way, when you are done eating and the characters have come and gone, you will be ready to leave.
Have fun - Tusker House was our favorite character breakfast of 6 on our last trip. We have an 815 ressie for our late May/early June trip. I can't wait!!!