SO07191 contains HOLDDATA information regarding RHDCEVBF.
For most sites, no action will be necessary. This article explains why.
CA IDMS r19.0
The HOLDDATA for SO07191 has this information regarding RHDCEVBF:
"After installing this PTF, please compile and link your existing RHDCEVBF program.
If RHDCEVBF is in any of your dictionary load areas, please use the IDMSDDDL utility with to update them with the new RHDCEVBF object module."
The first part about re-linking RHDCEVBF is only necessary if you have customized RHDCEVBF to add your own built-in functions.
(See Creating User-Defined Built-In Functions)
The second part is only necessary of you have your current version of RHDCEVBF in a dictionary load area and it needs to be replaced with the new version from SO07191.
If your RHDCEVBF is loaded from CDMSLIB, this is not necessary.
There is no good reason to run with RHDCEVBF in a load area so it makes sense to delete it from there anyway and use the version in CDMSLIB.
Most sites do not define their own built-in functions and do run their RHDCEVBF from CDMSLIB, and in that case no action is necessary.