diff --git a/target/linux/bcm27xx/base-files/lib/preinit/79_move_config b/target/linux/bcm27xx/base-files/lib/preinit/79_move_config
index c9fb59a64f..db5bf93b62 100644
--- a/target/linux/bcm27xx/base-files/lib/preinit/79_move_config
+++ b/target/linux/bcm27xx/base-files/lib/preinit/79_move_config
@@ -2,16 +2,20 @@
 
 . /lib/upgrade/common.sh
 
-BOOTPART=/dev/mmcblk0p1
-
 move_config() {
-	if [ -b $BOOTPART ]; then
+	local partdev
+
+	export_bootdevice && export_partdevice partdev 1 || {
+		partdev=mmcblk0p1
+	}
+
+	if [ -b "/dev/$partdev" ]; then
 		insmod nls_cp437
 		insmod nls_iso8859-1
 		insmod fat
 		insmod vfat
 		mkdir -p /boot
-		mount -t vfat -o rw,noatime $BOOTPART /boot
+		mount -t vfat -o rw,noatime /dev/$partdev /boot
 		[ -f "/boot/$BACKUP_FILE" ] && mv -f "/boot/$BACKUP_FILE" /
 	fi
 }