Update Add-VivaModuleFeaturePolicy.md

Updated IsUserOptedInByDefault parameter description

Author: knovichenko

exchange/exchange-ps/exchange/Add-VivaModuleFeaturePolicy.md

@@ -254,10 +254,10 @@ This parameter is available in version 3.8.0-Preview2 or later of the module.
 
 The IsUserOptedInByDefault parameter specifies whether user opted in by default by the policy. Valid values are:
 
-- $true: User opted in by the policy.
-- $false: User opted out by the policy.
+- $true: User is Opted in by default by the policy if the user has not set a preference.
+- $false: User is Opted out by default by the policy if the user has not set a preference.
 
-Only features that allow admins to enable and disable user controls by policy can use this parameter. If the feature doesn't support admins toggling user controls, the default value applies. See the feature documentation for more information.
+An optional parameter. This parameter can be used to override the default user opt-in value set in the feature metadata. This parameter can be only be set when -IsUserControlEnabled parameter is set to $true.
 
 ```yaml
 Type: Boolean