Docs: monthly reports (#25964)

* Docs: monthly reports

* Docs: version available

* Docs: feedback from Diana and Agnes.

docs/sources/enterprise/reporting.md

@@ -69,7 +69,7 @@ Hourly reports are generated once per hour. All fields are required.
 
 Daily reports are generated once per day. All fields are required.
 
-* **Time -** Time of day in 24 hours format when the report should be sent.
+* **Time -** Time the report is sent, in 24-hour format.
 * **Time zone -** Time zone for the **Time** field.
 
 #### Weekly
@@ -77,7 +77,17 @@ Daily reports are generated once per day. All fields are required.
 Weekly reports are generated once per week. All fields are required.
 
 * **Day -** Weekday which the report should be sent on.
-* **Time -** Time of day in 24 hours format when the report should be sent.
+* **Time -** Time the report is sent, in 24-hour format.
+* **Time zone -** Time zone for the **Time** field.
+
+#### Monthly
+
+> Only available in Grafana Enterprise v7.1+.
+
+Monthly reports are generated once per month. All fields are required.
+
+* **Day in month -** Day of the month when the report should be sent. You can select `last` for reports that should go out on the last day of the month.
+* **Time -** Time the report is sent, in 24-hour format.
 * **Time zone -** Time zone for the **Time** field.
 
 #### Never