Dell Unity: Regarding the behavior of Replication synchronization time shifting slightly from the RPO time. (User Correctable)

If the RPO is set to 1440 minutes (a day), the synchronization was expected to occur once a day, exactly 24 hours later.
However, the transfer occurred less than 24 hours after the last synchronization.

Example of synchronization time transition when RPO is 1440 minutes:

Time of last sync                 = 20xx-xx-16 13:00:00
Time of last sync                 = 20xx-xx-17 12:59:56
Time of last sync                 = 20xx-xx-18 11:24:30
Time of last sync                 = 20xx-xx-19 11:24:25
Time of last sync                 = 20xx-xx-20 11:24:21

This works as expected.

The synchronization time interval for asynchronous replication is controlled at the previous copy rate and the previous data transfer duration.

Synchronization time point = previous synchronization time point + RPO - delta
 
Delta was calculated based on the previous copy rate and previous data transfer duration.
The introduction of delta ensures that under most conditions, the changed data was synchronized to the destination array in one RPO cycle. 

As a result, the snapshot refresh timepoint is moved forward due to the delta.

If the goal is to synchronize at exactly the same time each day, consider manually synchronizing at a certain time, rather than adjusting at the RPO.

Note:
It is not possible to set up Cron within Unity, so consider running the uemcli command from an external client.

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