Timed Access Issues - next day unable to connect to 2.4Ghz

Hi

I have:

Airport Extreme 6G and two 4G Extremes.

The 6G is acting as the router to my Virgin Media Superb 2 in modem mode and the 4G are in Bridge mode connected to the 6G. One has Wifi on it and the other is being used next to the 6G as a switch for more LAN ports.

(as of March 2018)

Anyway ...

I setup Timed Access for my daughter aged 11 as she sits on Xbox Live and iPads too long. Basically its turned off at 21.30 every night.

My issue is this:

Today on Sunday the Xbox / iPad should be live until 21.30 at night. However at 10am the Xbox refuses to connect. It only has 2.4ghz Wifi and it shows as blocked as it won't accept the wifi.

I went over to the iPad to see its connected at 5Ghz fine. However when moving it to my 2.4Ghz network SSID it stated no password like the Xbox 360? WEIRD? So ... I then went back to 5Ghz on the iPad and then back to 2.4Ghz and this time it connected!

So with this in mind I tried the Xbox 360 three times (click try again) and it then connected to the 2.4Ghz Apple Extreme SSID. Why not the first time?

(Yes I have checked the rules in the Timed Access and I have exported and imported it to the other Wifi 4G Bridge Extreme. I may try to add it to the switch bridge with no wifi but this should matter)

Any ideas?

The fact that it does it on the iPad and Xbox 360 must be the Apple Extreme is refusing these although the rule states 00.00 to 21.30 on Sundays?

Thanks