uci_load() {
	local PACKAGE="$1"      # <- THIS LINE IS MISSING.. surely caller is not supposed to set it.
	config_load "$PACKAGE"
	local PACKAGE_BASE="$(basename "$PACKAGE")"
	[ -f "/tmp/.uci/${PACKAGE_BASE}" ] && {
		. "/tmp/.uci/${PACKAGE_BASE}"
		config_cb
	}
}

....
Note how uci_load is used by other funcs, i.e. uci_set:
   uci_load "$PACKAGE"
....