Just an update in case someone else is wondering. We parked at 7:30 but we ended up about 20 minutes late for our reservation. The good news is that they allow you to be 1/2 hour late
Our lateness was mostly because the monorail does not start running until 8:30 am (park opened at 9). We had to wait 15 mins for the ferry.
Anyways, we really enjoyed our food at BOG breakfast!