XB8 settings conflicting with Apple devices

I upgraded to an XB8 approx 3-4 weeks ago.  Since then many of our Apple devices are having trouble.  They will randomly disconnect even though signal strength appears strong, and then when trying to manually reconnect the device will say "can not connect".  I am then forced to "Reset Network Settings" on my Apple device, and then manually connect to the WiFi network, retype in password, and then a strong connection is restored.  This is happening on multiple iPhone and iPads specifically, all of which are very new (< 1-2 years old).

A little about network setup.  XB8, two 2ng gen Comcast Pods on the upper floor of the house, all frequencies cast the same network name, but the 6Ghz has a different security setting than the 2.4 and the 5 to help maintain connectivity with older WiFi devices in the home.  MOCA is turned on and being utilized for some old hard wired devices in some of the bedrooms (TiVos).  This setup had no problems with the XB7 that this router replaced.

Have rebooted the router countless times and I can't change the 6Ghz security settings down to WPA2 like I have for the 5 and 2.4 frequencies.  Not sure if that is related or not.  Firmware version is CGM4918COM_7.6p9s2_PROD_sey

Would appreciate any help.