Why is the subscription status in the Whoscall app different from the status of the App Store plan after adjusting the subscription plan?

Based on the term of use of the App store, if you choose to upgrade when adjusting the plan (such as upgrading from "AD-Free Plan" to "Premium Plan"), the change will take effect immediately; if you choose to downgrade when adjusting the plan (such as upgrading from "Premium Plan" downgraded to "AD-Free Plan"), the change will not be displayed until the end of the original current subscription service period.