ENERGYINTEROP-492 for background.
ResourceTargetType should be renamed EiTargetType; wd29 WIP version includes emixInterfae, groups, resourceIDs, and SHOULD contain optional VenIDs (0..*) as well.
Distribute (Event || Quote || Tender) should have eiTarget included.
To cancel such an (Event || Quote || Tender) eiTarget has to be an optional element of the payload.
In the case of a VEN given the EiCreateEvent via point-to-point messages, eiTarget is not needed – and the respective VEN gets the Cancel.