The question
A set of individual project plans does not automatically create a program plan. Look at the connections between workstreams and clarify which decisions need to be made together.
The approach
Map dependencies, agree ownership and establish a practical escalation path. Keep reporting focused on the information decision-makers need, including uncertainties that could affect other teams.
The decision
Review the overall delivery sequence as circumstances change. Keep the organisational objective visible and explain why a change is needed, who owns it and what it affects.