How can we detect app subs renewals and how can we fast forward app renewals/cancellations?
Hi @Jaspreet_Singh 
Two separate questions here, so I’ll take them in order.
For detecting subscription renewals, subscribe to the app_subscriptions/update webhook topic. The docs describe it as firing whenever an app subscription is updated, and a renewal updates the subscription’s billing period, so this is the topic to watch. You can register it in your app config file or via the webhookSubscriptionCreate mutation. As a backup, you can poll the AppSubscription object and check the currentPeriodEnd and status fields to track where a subscription is in its lifecycle.
There’s no mutation to skip ahead in an app billing cycle. Shopify manages the 30-day (or annual) cycle internally with no way to accelerate it. What you can do is pass test: true on appSubscriptionCreate so the subscription goes through the full flow without real charges (if you’re using managed pricing on a dev store, test subscriptions are created automatically). To simulate lifecycle transitions during testing, cancel a subscription with appSubscriptionCancel and create a new one to trigger status changes. For testing trial expiry specifically, create a subscription with a short trialDays value (e.g., 1) so the transition to paid happens quickly rather than extending a long trial.
Let me know if you have a specific scenario you’re trying to test and I can point you to the right approach.