HA msync.log - many errors for "cmd 'ipset -D hostset" or "sesid:-1:evm slot has NULL for sd 10"

I've a new XGS HA A/P cluster running on v20.0.1. The cluster is a migration from a retired XG system. All is running and looks fine so far.

When checking logs, I found in the HA logs that this is filling with errors. Mostly the errors are always of the same type:

Fri Jun 21 18:35:32 2024:653114Z:3242:MAST:MAST:ERROR:event.c:566:handle_event: not found in get_evm2list() for sd 10
Fri Jun 21 18:35:32 2024:692530Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -A hostset wcfqdn,567,0,23.', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:32 2024:696762Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -A hostset wcfqdn,1559,0,52', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:37 2024:167965Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset wcfqdn,1559,0,52', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:38 2024:533323Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset wcfqdn,1559,0,52', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:39 2024:989615Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 12
Fri Jun 21 18:35:39 2024:994205Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 12
Fri Jun 21 18:35:40 2024:007395Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 12
Fri Jun 21 18:35:40 2024:015974Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -A hostset fqdn,580,0,52.92', cli_fd 12, serv_fd 13
Fri Jun 21 18:35:40 2024:025462Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:038884Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:043258Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset fqdn,580,0,52.92', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:40 2024:043281Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 11
Fri Jun 21 18:35:40 2024:051793Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset fqdn,580,0,52.21', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:40 2024:056171Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:065146Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:082952Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:104758Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:113369Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:121945Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:126222Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:130435Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:134911Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:139612Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset fqdn,1850,0,52.2', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:40 2024:153000Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:204748Z:3242:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset fqdn,1851,0,52.2', cli_fd 10, serv_fd 11
Fri Jun 21 18:35:40 2024:204769Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 11
Fri Jun 21 18:35:40 2024:299597Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Fri Jun 21 18:35:40 2024:303765Z:3242:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
..
..
..
Sat Jun 22 08:16:03 2024:453363Z:3229:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Sat Jun 22 08:16:03 2024:567705Z:3229:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset wcfqdn,342,0,17.', cli_fd 10, serv_fd 11
Sat Jun 22 08:16:03 2024:980847Z:3229:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Sat Jun 22 08:16:05 2024:496076Z:3229:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Sat Jun 22 08:16:05 2024:664210Z:3229:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -A hostset fqdn,1849,0,52.9', cli_fd 10, serv_fd 11
Sat Jun 22 08:16:06 2024:968134Z:3229:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Sat Jun 22 08:16:07 2024:026089Z:3229:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 10
Sat Jun 22 08:16:07 2024:244968Z:3229:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 12
Sat Jun 22 08:16:09 2024:072476Z:3229:MAST:MAST:ERROR:event.c:572: error found for cmd 'ipset -D hostset wcfqdn,417,0,213', cli_fd 10, serv_fd 11
Sat Jun 22 08:16:09 2024:072506Z:3229:MAST:MAST:ERROR:sync.c:498:sesid:-1:evm slot has NULL for sd 11

Currently I have no physical access to the old appliance to check if these logs have been there before the migration.

So I'd like to know what's the reason for the errors and if it is an expected log behavior? Do you have it also in your HA cluster logs?