SP12 upgrade problem

Can someone please explain to me if I understand this correctly:

SCS03 - SAP central instance (is this the correct understanding)

JC02 - Java central instance (is this the correct understanding)

During the upgrade of the Java J2EE engine upgrade to SP12, when the question is asked of the path toy our central instance. Which one do I issue, the SCS03 one or the JC02 profile.

thanks