I'm currently using the Telus Arcadyan (Wi-Fi Hub) and recently noticed the 2.4 Ghz Wifi Band was "greyed" out in the GUI (couldn't make any changes to it under it's tab under Wifi settings). Both the 5 Ghz bands were fine. I had just got this modem so I called the tech that dropped it off and he said to do a factory reset and see if that clears it up--that option worked but I'm wondering if this should be happening to a brand new modem or if I should be asking them to replace it with another new one.
If the device is new it's common to have a firmware update pending. It's also common for any firmware update to require a reset before it works properly.
Unless you are noticing other issues your device is probably fine.
Thanks for the follow-up and info, it's appreciated. When I first plugged in the new router I logged into the GUI to update the passwords and checked a few other settings, the firmware version matched what was shown after the reset. So I don't think that was updated but since then the 2.4 Ghz band is ON. I'm guessing something maybe didn't upload properly the first time. Thanks again for your feedback though, @xray take care!