Upgrading to CU3, quick question - more questions after upgrade

Question

So I am finally getting around to installing CU3 to our environment, upgrading from the base SCCM 2012 R2 install.  I am running SCCM in a 1 CAS and 3 Primary server environment.  I'll be upgrading the CAS first, and the update gives the option
of importing the client packages for upgrades into SCCM Software Library.  The question is, is should I be doing this on the CAS, as our CAS does not have any clients reporting to it?  Obviously I'll be importing them into the Primary sites, and
I wasn't planning on importing them into our CAS, but wanted to verify that is the correct action.

Answer 1

So I updated the CAS, and the primary sites, and I deployed the client upgrade packages to about 25 test machines. All the test machines received and updated successfully.  They have the updated version of x.1401 on the client sided, however it has
been almost 24 hours for some, and I only see three clients in the Device Collection node that's in the SCCM console that are reporting the new client version.  The ones that have reported back are those that have performed a hardware scan after the update.
 Is this normal? 
Also when I go into Administration > Sites and look at the version being reported here, it is also on the old version, despite being correct in the About System Center Configuration Manager, and seeing the CU registry key reporting "3".  Is
this normal?