Thanks for your response.
So, there's a open ticket on this since Oct 18th. The utility job has been failing every night.
There're no tables added to replication (so no ALTER DATA CAPTURE..) at that time of the night and there are no REFRESHes done at that time of the night. It appears that under certain circumstances the logreader thread is failing to COMMIT.
Interesting, I know an APAR that was issued for the case of log reader holding long running transactions.Release Notes for IDR 11.4 for Db2 for z/OS Remote Sourcespecifically :September 27, 2019
Enhancements in IDR 18.104.22.168-5506 for Db2 for z/OS remote source