Turn off repeater:

uci set glconfig.repeater.autoconnect='0'
uci commit glconfig

uci set wireless.sta.disabled=‘1’
uci commit

wifi restart

Turn on repeater:

uci set glconfig.repeater.autoconnect='1'
uci commit glconfig

uci set wireless.sta.disabled=‘0’
uci commit

wifi restart

Besides, you can re-assign the switch function via modify the script /etc/init.d/initswitch.