SAP SD - Control Repeat Output in the Cancelled Invoice during Org Invoice Cancellation.

We are facing challenge after enabling the Multiple Issue functionality for one of the Invoice Output where we send PDF attachment via email. As the Multiple issue function will retrigger the Output whenever there is a change in the Invoice Document which is valid. Our case is,

1. Customer Invoice *XYX* created in Nov 2017 - Output Triggered for the first time. This is ok.

2. Customer Invoice *XYZ* was cancelled in Dec 2017 and hence a cancellation Invoice created. Here, as per std, a Cancellation Indicator is updated automatically in the Customer Invoice *XYZ* which is a change and hence as per Multiple Issue Function, the Output retrigger in the Customer Invoice *XYZ*. How to control this repeat output during Cancellation Indicator update which the User do not want.

Pls share if there are any specific technical developments can be done to manage and exclude "Cancellation Indicator" update validation before Repeating the Output.