Hi, sorry if I caused you any confusion. The point of override is to allow you to assign a WLAN a different VLAN. You have to create different WLAN groups and then apply the overridden one to the appropriate AP. This will do exactly what you want.
So lets say we have AP1 in the lobby and you want SSID#1 with VLAN#100. Then you want AP2 in warehouse to have SSID#1 but with VLAN#200. You could create 2 WLAN groups, one with the default configuration and then another with SSID#1 but click override and put in VLAN#200.