Problem with clients not supporting all channels

We have some public locations where we provide WiFi using CAPsMAN and wAPac.
There are international travellers in some areas, and many of those can not connect to our AP’s on 5GHz because their clients don’t support some of the channels automatically selected by CAPsMAN.
Is there a country-code in CAPsMAN that limits the channels to just 2.4GHz and the oldest most basic 5GHz channels, or what is the best way to configure this to ensure that all devices will work?