"Some wired connection" was a typo, I meant "some wired connections", and was referring to the wired ports on the back of your Orbis. Just to say that the Orbi wired ports are available to use, of course, as well as the wireless AP when the Orbi is in AP mode.
The Orbi is designed to be in either Router or AP mode, depending on what serves you best...I got the Orbi for it's great wireless coverage, so AP mode is fine with me. It's worth its cost for that, as far as I'm concerned. And yes, the wireless dedicated backhaul is still fully used between the Orbi router unit and the Orbi satellite unit. So you're using the full wireless features of the Orbi in AP mode *smile*.
Here's a Netgear article on how to go from "Router" mode to "AP" mode with the Orbi:
https://kb.netgear.com/31218/How-do-I-configure-my-Orbi-router-to-act-as-an-access-point
First time I switched from Router mode to AP mode, I followed the above article, generally speaking. Just to help with the surprises, when you have the Orbi in router mode with the gateway also in router mode and connected to your cable gateway just before you switch it to AP mode, assuming that the cable gateway takes the IP address 192.168.1.1, which it most likely will, the Orbi will automatically shift its own IP address to somewhere in the 10.0.*.* range to avoid conflicting with the cable gateway IP. You don't really care about that. You'll also be double NAT'ing until you switch the Orbi to AP mode, and you don't care about that, either *smile*. Those are transitional things. When you follow the directions above and switch the Orbi to AP mode, the Orbi router and satellite units will be assigned DHCP addresses by the cable gateway. And DHCP, etc. will be turned off on the Orbi, of course.
If any questions come up along the way, feel free to ask. I have a Netgear R7800 as my "main router" (for wired connections only) where you have your cable gateway...I find the Netgear R7800 quite a capable "main router". And the wireless from the Orbi in AP mode provides better coverage than the R7800 did when I was using that in full wireless router mode. So I'm pretty happy with this arrangement.