Released: January 2022 Exchange Server Security Updates

topracingit seems the problem is rather unrelated to the update, but rather your configuration. it seems that you are receiving spam messages, but don't know where to look for them. usually if you know the rcpt address you could try with sth like:

Get-MessageTrackingLog -start 04/02/2021 -recipient Email address removed | Select MessageSubject,Timestamp,Sender,*ClientIP*

after you know the src, it's worth to:

- perform check of receive/send connectors and see if you have minimal required ip scope in there to not accept communication from not needed sources and that auth is required on all communication ( with known exceptions )

- check your spam filter configuration/logs to see if any message happen to slip through your policy

sorry, but it's hard to be specific with this lil info.

Regards, Hubert