Why subscription Next Billing Date is not updated during Renewal Order generation? When will it be updated?
Subscription Next Billing Date is updated when Billing order is generated for subscription, which takes recurring for subscription period. Billing order generation time depends on subscription Billing settings, such as Billing Period Type, Billing Period, Charge for Subscription. For more details on these setting please refer to Billing Models section of our documentation. Also notice that some Billing Orders are not seen in PBA CP, more detailed information on such orders can be find in this article - No billing order is created for the subscription.