- Clarify change to default behavior

- Add note on restarting pods during change of flag

keps/sig-storage/3141-prevent-volume-mode-conversion/README.md

@@ -417,7 +417,10 @@ unauthorized conversion of the volume mode.
   - Describe the mechanism: Out-of-tree flag named `PreventVolumeModeConversion`, 
   which will be enabled in `external-provisioner` and `external-snapshotter`.
   - Will enabling / disabling the feature require downtime of the control
-    plane? No
+    plane? `external-provisioner` and `external-snapshotter` will need to be 
+  restarted for the changes to take effect. This means that there will be a few
+  seconds of downtime until the newer Pods are Running. There will not be any 
+  effect on the previously running applications.
   - Will enabling / disabling the feature require downtime or reprovisioning
     of a node? (Do not assume `Dynamic Kubelet Config` feature is enabled).
     No
@@ -428,6 +431,9 @@ Yes. Users without requisite privileges cannot alter the volume mode of `VolumeS
 when it is being used to create a `PVC`. Users with privileges need to add an 
 annotation to the corresponding `VolumeSnapshotContent` instance if they
 require the volume mode to be converted.
+The default behavior does not make any validations prior to provisioning a volume.
+The volume mode can be converted by any user when a `PVC` is created from a 
+`VolumeSnapshot`.
 
 ###### Can the feature be disabled once it has been enabled (i.e. can we roll back the enablement)?