Problem retrieving info of Plans within Follow-up action

We have created a follow-up action in the server (using operationParticipant extension point), assigned it to the Save/Plan action (com.ibm.team.apt.server.saveIterationPlan) and configure it to be run when a user saves a Plan.

Everything works fine and when the operation takes place we are able to reach our "run" method

    public void run(AdvisableOperation operation,
                IProcessConfigurationElement participantConfig,
                IParticipantInfoCollector collector, IProgressMonitor monitor)
                throws TeamRepositoryException {...}

from the implementation Class of the participant:
public class followupH extends AbstractService implements IOperationParticipant { ...}

Within our "run" method, we need to access some information about the recently saved plan, such as Plan id, Plan name, etc. Basically, the information contained in a "IIterationPlanRecord" should be fine for us.

Here comes our problem, we are not able to extract this info.
A usual "operation.getOperationData()" in the AdvisableOperation of the "run" method gives us just a String Object with the text"[modify/plan]". No NewStateItem nor OldState nor UUID... we are not able to extract any information from "AdvisableOperation operation".
Anyone working with advisors/participants in Plans could give us a hint?

Thank you very much in advance!