Hello friend,
I've install OpenWRT 20.02.1 on Linksys WRT1900ACv2, After that I ran into a problem with 2.4GHz WiFi with WPA(1-3) security. On some device (Eg. Nokia 8 can't connect 2.4GHz WiFi, can connect only on 5GHz WiFi).
(It's working fine on WRT1900ACv2/19.07.8 or RM-AC2100/20.02.1)