As PM/SA/stakeholder would like to recognize in which PI a program issue (feature, enabler) is planned and see directly deviating planning from teams:

Example:

A feature is planned in the roadmap for PI22. The tag in the feature appears "green".

A team is now planning an additional story (child of feature) in a leading PI (PI21) and an additional story in a later PI (PI23).

The feature shows the PI tag PI21 "blue", PI22 "green", PI23 "blue".