Can the Avalon Openwrt version running on TL-WR703N be converted back to standard Openwrt?
I have bricked 6 devices so far trying.

I picked up a bunch of Avalon TL-WR703N and each one keeps getting bricked as I try to recover them back to a standard openwrt firmware so I can then upgrade using my own image builder build.

https://forum.openwrt.org/viewtopic.php?pid=254109#p254109

I tried today, the u-boot method but am getting nowhere.

Picked up the files mentioned in this post;
https://forum.openwrt.org/viewtopic.php?id=48169

Gave it a try but ended up with an error;

3840 -rw-r--r--    1 root     root       3932160 Jan  1 10:05 factory.bin
    64 -rw-r--r--    1 root     root         65536 Jan  1 10:06 uboot_for_tp-link_tl-wr703n.bin
     4 -rw-r--r--    1 root     root            66 Jan  1 10:06 uboot_for_tp-link_tl-wr703n.md5

# md5sum uboot_for_tp-link_tl-wr703n.bin
5799189400ee774c45bd0bfb79ef9ffd  uboot_for_tp-link_tl-wr703n.bin

# dd if=/dev/mtd0 of=uboot_orig.bin
256+0 records in
256+0 records out

# cp uboot_orig.bin uboot_new.bin

# dd if=uboot_for_tp-link_tl-wr703n.bin of=uboot_new.bin conv=notrunc
128+0 records in
128+0 records out

# mtd write uboot_orig.bin "u-boot"
Could not open mtd device: u-boot
Can't open device for writing!