I used the image “openwrt-mvebu-cortexa53-globalscale-espressobin-sdcard.img.gz” for sysupgrade and it worked the same way we do it for ext4 images on x86.
Furthermore, Perl and Squid were successfully compiled after OpenWrt maintainers responded to the bug report.
Only wait is to get the changes merged to trunk.
Technical specification tables can not be displayed on mobile. Please view on desktop