This was fixed in 4.7.3
Verified 4.7.0-0.nightly-2021-04-01-061355 has ovn2.13-20.12.0-24.el8fdp.x86_64 which should fix the issue as per https://bugzilla.redhat.com/show_bug.cgi?id=1929978#c3 No "failed in flood_remove_flows_for_sb_uuid" errors present in logs. all ovnkube-node pods are healthy.