I was looking at this file https://github.com/openwrt/openwrt/blob/v23.05.0-rc2/package/firmware/ipq-wifi/Makefile and it looks like it downloads the board files.
Since wax620 is not available in the repo it will always be 1KB.
It doesn’t make sense to me… I’m clearly missing something here.
Edit: yeah, I believe we have to use the qca tool