Edited a message already send to a particular person. Now selected entire group & Saved the message. It is noted that entire gp member not able to see that message.

Login as a User, U1
Create a message
Select checkbox for Individual Group Members & select a user ( U2).
Save & Send message.

Go to Edit mode.
Uncheckbox the check box for Individual Group Members & select the check box for Entire group and click SAVE button.
Login as U2.
Check the messages under the Me radio button.
The newly edited message is shown.

Now login as U1 or U3 ( who is also a member of that group).
Check the message tab.
The newly edited message is not displayed ( evenif that messsage was Saved after selecting the check box for 'Entire group' ).