Upgrading clients to 12.1.6.1A

Hello - I am about to upgrade our clients to the latest version of 12.1.6.1A.  I have created new install packages and have assigned the new packages to the different OUs by deleting the old install package assigned to the OUs and replacing with the new packages thru the Clients tab.  (see attachment).  Is this a correct way to upgrade the clients?  or do I have to go thru the admin-install packages tab and auto upgrade the OU?  I know there are various ways to do things.  I also did not configure the schedule.  When will the upgrades begin to go out to clients?

thanks

Solo