From the z/OS 3.1 MVS JCL Reference manual:
Location in the JCL
You can specify the COND parameter on any EXEC statement in the job. However, the system evaluates a COND parameter on the first EXEC statement in a job as false.
Location in the JCL
You can specify the COND parameter on any EXEC statement in the job. However, the system evaluates a COND parameter on the first EXEC statement in a job as false.