Update Set-ActiveSyncOrganizationSettings.md

Issue #3076

Author: chrisda

exchange/exchange-ps/exchange/devices/Set-ActiveSyncOrganizationSettings.md

@@ -111,7 +111,15 @@ Accept wildcard characters: False
 ```
 
 ### -DefaultAccessLevel
-The DefaultAccessLevel parameter specifies the access level for new devices. Valid values are Allow,Block or Quarantine. The default value is Allow.
+The DefaultAccessLevel parameter specifies the access level for new and existing device partnerships. Valid values are:
+
+- Allow (This is the default value)
+
+- Block
+
+- Quarantine
+
+If you change this value from Allow to Block or Quarantine, all existing connected devices are immediately affected, unless the devices are subject to device access rules or individual allow or block list entries.
 
 ```yaml
 Type: Allow | Block | Quarantine