Update Features-Mvc-Core-Subscription.md

Author: Musa Demir

docs/en/Features-Mvc-Core-Subscription.md

@@ -18,6 +18,15 @@ After all, invoices for payments related to subscription can be generated. You c
 
 AspNet Zeros subscription system allows using two payment gateways, one is [PayPal](https://www.paypal.com) and the other one is [Stripe](https://stripe.com/). You can configure both payment gateways in the `appsettings.json` file in ***.Web.Mvc** project.
 
+When subscription of a Tenant is about to expire, an email is sent to email address of the tenant to remind this expiration. This job is handled in **SubscriptionExpireEmailNotifierWorker.cs** background worker. This worker runs once in every day and sends email to tenants whose license will expire after N days later. The day count of N is stored in a setting named "**App.TenantManagement.SubscriptionExpireNotifyDayCount**" and its default value is 7 days. You can change it in **AppSettings.cs** class in *.Core project.
+
+When the subscription of a Tenant is expired, **SubscriptionExpirationCheckWorker.cs** (it is localed next to SubscriptionExpireEmailNotifierWorker.cs) comes into play and executes the logic below:
+
+* If **WaitingDayAfterExpire** is set for the Edition of the tenant, ASP.NET Zero waits for **WaitingDayAfterExpire** days to end Tenant's subscription.
+* If **"assign to another edition"** option is selected for the Edition of the Tenant, tenant will be moved to the fallback edition.
+* If "**deactive tenant**" option is selected for the Edition of the Tenant, tenant will be disabled and will not be able to use the system.
+* If the subscription expires for a tenant who subscribed for trial usage, the tenant will be disabled and will not be able to use the system.
+
 ## Next
 
 - [PayPal Integration](Features-Mvc-Core-Subscription-PayPal)