“Subscription plans” refer to the billing relationship plan details provided by a mobile carrier through [SubscriptionManager.setSubscriptionPlans()
](https://developer.android.com/reference/android/telephony/SubscriptionManager.html#setSubscriptionPlans%28int, java.util.List<android.telephony.SubscriptionPlan>%29).
All device implementations:
SubscriptionManager.setSubscriptionOverrideCongested()
](https://developer.android.com/reference/android/telephony/SubscriptionManager.html#setSubscriptionOverrideCongested%28int, boolean, long%29), from the mobile carrier app currently providing valid subscription plans.