U7621-01 AX modem Openwrt Image Creation

Hello,

For U7621-01-AX Boards, I want to learn openwrt image configuration.

As I can see on OpenWrt firmware downloads, there is no official sysupgrade file. U7621-06 (sysupgrade 17.07) and U7621-01(snapshot) firmware in Openwrt website, are not uploaded to the board, incompatible. I configurated my image file this is also not uploaded to the board.

As I can know, I could create image file by choosing u7621-06 device type and correct wifi ax modules on SDK. But this does not work, What could be wrong?

Thank you.