Early morning ADR and International Gateway entry

We are staying at the Boardwalk in the end of October and have an 8 am ADR for Garden Grill. How early will we be allowed to enter through the International Gateway entrance? How long should we expect it to take to walk leisurely to GG?

Also, this is a day the park opens at 9am.

We just did this in April. We got there at 7:30 and they let us in. Don’t know if we could have gotten in any earlier. I would say it took us about 15 minutes to walk to Garden Grill, but we kept stopping to take pictures of the Flower & Garden Festival gardens and topiaries since there was no one else there!