That is correct. Unless....the lock is in range of your home hub. My front door is, while my back door is no where near it. The August apps works ok form us though. The Auto Unlock has worked really well too.
The only option I really have is to have 2 hubs. One being Apple TV in front and an iPad on the wall in the back.
I just don’t understand why it’s so hard or what the requirements are for HomeKit over WiFi. No one seems the be able to explain it...