BillingStatus.md in fastly-6.0.1

- old
+ new

@@ -3,9 +3,9 @@
 ## Properties
 
 | Name | Type | Description | Notes |
 | ---- | ---- | ----------- | ----- |
 | **status** | **String** | What the current status of this invoice can be. | [optional] |
-| **sent_at** | **Time** |  | [optional] |
+| **sent_at** | **Time** | Date and time in ISO 8601 format. | [optional][readonly] |
 
 [[Back to API list]](../../README.md#endpoints) [[Back to README]](../../README.md)
 