update maintenance window explanation

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cc: @scott-kim-sql @dimitri-furman

Author: WilliamDAssafMSFT

articles/azure-sql/database/maintenance-window.md

@@ -37,8 +37,10 @@ By default, Azure SQL maintenance policy blocks impactful updates during the per
 
 You can further adjust the maintenance updates to a time suitable to your Azure SQL resources by choosing from two additional maintenance window slots:
 
-* Weekday window, 10PM to 6AM local time Monday - Thursday
-* Weekend window, 10PM to 6AM local time Friday - Sunday
+* **Weekday** window: 10:00 PM to 6:00 AM local time, Monday - Thursday
+* **Weekend** window: 10:00 PM to 6:00 AM local time, Friday - Sunday
+
+Maintenance window days listed indicate the starting day of each eight-hour maintenance window. For example, "10:00 PM to 6:00 AM local time, Monday – Thursday" means that the maintenance windows start at 10:00 PM local time on each day (Monday through Thursday) and complete at 6:00 AM local time the following day (Tuesday through Friday).
 
 Once the maintenance window selection is made and service configuration completed, planned maintenance will occur only during the window of your choice. While maintenance events typically complete within a single window, some of them may span two or more adjacent windows.