Insights into duplicate records seen in snapshot & logical replication slot.

Hi,  I am using postgres version 15.5 along with debezium to do CDC using logical replication slot after the initial snapshot of the db is complete.  Recently, observed a few cases where a record in a table showed up both via snapshot as well as from the replication slot. (this was a insert dml).

The understanding is that any dmls in a transaction has to either fall into the snapshot phase (as its a consistent snapshot done using the id returned during the replication slot along with repeatable read) or into the streaming phase , as read from the replication slot.
This issue is also not reproducible consistently, looks like a race condition. Am i stumbling upon a bug?

TIA