2957309 - Adding a db to HADR fails with "The maintenance user 'Unknown' was expected to be aliased to the database owner (dbo).." - SRS

Adding a new database to HADR with or without the force option fails with the following error:

1> sap_update_replication add_db, MYDB, force
2> go
TASKNAME           TYPE                             VALUE
------------------ ----------------------------- -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Update Replication Start Time                     Mon Aug 03 18:36:37 EDT 2020
Update Replication Elapsed Time                00:00:00
UpdateReplication  Task Name                    Update Replication
UpdateReplication  Task State                     Error
UpdateReplication  Short Description          Update configuration for a currently replicating site. 
UpdateReplication  Long Description           Verifying the distribution mode of HA hosts. Could not execute the command if the distribution mode is different.
UpdateReplication  Failing Command Error Message The maintenance user 'Unknown' was expected to be aliased to the database owner (dbo) of 'MYDB' on host 'myhost260.xxxx.xxx.xxx' port '50722', but it is not aliased.
UpdateReplication  Corrective Action           Use command 'sp_addalias Unknown, dbo' to alias 'Unknown' to the database owner (dbo).
...

• SAP Adaptive Server Enterprise (ASE) 16.0 SP03 PL08 HF1
• SAP Replication Server (SRS) 16.0 SP03 PL08 HF1
• High Availability Disaster Recovery (HADR)

restart, reboot, recycle, RMA , KBA , BC-SYB-REP-SAP , Replication with SAP Suite / SAP BW , Bug Filed