Setting "atime" when Retention Lock is not installed ?

I’m working with a customer to move Centera data to a Data Domain CIFS.  Retention lock is NOT installed and enabled on the DD Mtree.  This is a newly created Mtree and CIFS share and is the first CIFS on this DD in the environment.

I am trying to set the "atime" (lastaccessedtime) on files programmatically but it does not work on the DD CIFS.  Setting the atime in the future is an industry standard way to set retention.

I've run some simple tests using Windows RoboCopy with the "/COPY:DAT" settings to preserve file attributes and times.  That fails to preserve atime (lastasccesstime) as well.

Does anyone know if DD “Retention lock” would be required on a DD CIFS just to modify the atime on a file ?

After doing some more research I've found that some OSes disable atime tracking by default.  Does DDOS do this and if so how would it be enabled ?

DD is running DDOS 5.7.

Any help would be greatly appreciated

Jay R.