How to find 5Ghz backhaul channel used on Orbi RBK53?

Hello,

Does anyone know what the 5GHz backhaul channel is on the Orbi RBK53 mesh wifi system which it uses to communicate with each other? Or how I find this info in the web settings for the mesh wifi system (ie orbilogin.com page)?

I installed it recently and it is working great with normal devices but I'm in the UK and have Sky TV. The Sky TV (Cable/Satellite) uses a Sky box on ground floor but uses it's own mesh wifi system to connect to Sky Q mini boxes on two other floors. So you connect the Orbi wifi to main Sky box which then communicates its own internal signal via 5GHz to other two boxes. It is the two Sky Q mini boxes that I'm having issues with as there appears to be interference /connection break outs.

I've been told that Sky mesh system uses 5GHz  range of Ch36 to 52 (apparenty default is Ch36 80MHz). I've been told by experts in the Sky community forum that this setting can be switched to use Ch36 to 44 or CH44 to 52 by choosing the 40MHz option. 

I've noticed that my Orbi is also using Channel 36 for the wifi signal on 5Ghz, I can only switch it to 40, 44 or 48. 48 seems like the most sensible option to do as then can switch the Sky mesh to use the lower range of Ch 36 to 44. But I have no idea what the Orbi backhaul 5GHz channel is?

I have looked at the settings page and the only setting I can find under advanced is CTS/RTS Threshold (1-2347) set at 2347 under 5GHz. But don't think this is the same thing. Anyone know what the default channel or range is for the backhaul 5Ghz wifi on RBK53?

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Orbi RBK53 - router + 2 satellites triband

Router Firmware Version V2.3.5.30