Problem with linksys wrt1900ac v1 sysugrade to 21.02 not supported?

[hnyman]

Please read

OpenWrt 21.02.0 - First Stable Release

Like the error message says, you need to use the "factory image" instead of the sysupgrade image. You should be able to flash it by selecting the "force upgrade" there. And unselect the "keep settings". The underlying reason is explained in that error message that you see: Linksys had defined too small partition for the new kernel versions (used in 21.02 and master) for WRT1900ACv1 (mamba) and WRT32X (venom). So, the kernel partition has been enlarged for those two, but that prevents using t…