Updates after SP1

Hi all

I am currently deploying an Exchange 2013, and want to update to latest level.

Normally, they are called CU1 for RTM, CU1 for SP1 etc.

But does the list reflected here:

http://technet.microsoft.com/en-us/library/hh135098(v=exchg.150).aspx

indicate that AFTER SP1 i need CU5 ?! and not as i would expect CU1 for SP1

Hope for an answer

Kenneth
Denmark