Let's assume I have auto renewable subscription with active subscribers. I would like to remove the subscription from sale - so uncheck the checkmark "Cleared for sale" in AppStoreConnect. The question is if there will be sent any server to server notification for this case, which indicates that the subscriptions (for the mentioned subscribers) won't renew anymore at their expiration date? I looking some basis on which I can inform users that the subscription will stop at the next expiration date.
Subscriptions server to server notifications for subscription removed from sale
About that, see Handling Subscriptions Billing
To view the number of existing subscribers, go to ASC..<that app~IAP> 'Sales and Trends'.