Welcome to the forum. I would imagine that dealers will start to see some inventory by the end of this month. If you were to reach out to a local shop they could probably give you a more definite timeline.
I live in Cincinnati, and stopped by our dealership during the summer and was told they would be out in September. Mid-October I call around to the (3) Hyundai/Genesis in the area.
1st dealer that said they would be delivered in September is now saying February 2019.
2nd dealer said they would probably get a delivery 1st quarter 2019.
3rd dealership said they had no idea. They were a smaller dealership and low volume so they would be pretty low on the list to get the G70s.
When I priced one out on line, the website said the closest dealer to me was in Michigan. Checked their website and they did have a few G70s. So I am guessing they are delivering to the "Genesis" dealers first.