Currently the replication slot for the source connector is becoming "lost" in stage. After some investigation this is due to the outbox table being idle for too long. This will fill the WAL in postgres and cause the replication slot to be lost.

To fix this, configure the source connector to have a heartbeat. This will trigger the WAL to progress and prevent further issues while the outbox is idle. This shouldn't be an issue once dual-writes are enabled.