work orders on Integrated Activitiy Plan

Some maintenance Tasks are relevant for the integrated activity plan. The integrated activity plan is a Long term plan which shall include the most relevant activities for the Business across all departements (the integrated activity plan is managed outside sap in a Project Management Software).

How can workorders be flagged so that the planner can identify them as relevant for the integrated activity plan. Planner will filter IAP WO to update the integrated activity plan.

I was looking into revisions (IAP Revision) but work orders - as far as I know- can only be part of one Revision. One way might be to have a custom field on work orders. Workorder types and activity types we use for maintenace Task types (i.e. preventive, corrective, ....) so I would prefer not to use them for IAP relevant work orders.

Any ideas to solve the Problem?