ath79/generic tplink archer a7 v5 (used as dump AP): successfully upgraded from 19.07.3
ramips/mt7621 zbt-wg3526-16M (router): lock ups on 19.07.5, possibly related to https://forum.openwrt.org/t/mtk-soc-eth-watchdog-timeout-after-r11573, reverted to 19.07.3