Using the PI-SDK I am able to look up aliases for unit-batch items. Among these is the alias for the tag, the ActivePoint. It is not clear to me how to do this for sub-batch items that are children of unit batch items. The sub-batch item does not contain a PIUnit property with which to use for looking up aliases. How do I look up Aliases, in particular the one with the tag name, for sub-batch items?
As an example here is a screen shot of the batch database where I followed the course material to input the "My Pulp Co." process. I am trying to get to the SubBatchSupport->Operations->Aliases->ActivePoint=PP:Digest1.OP.