Transitioning to RHEL5 from RHEL4

I have a subscription for RHEL4 on my main server.  I am planning to
upgrade that machine to RHEL5, probably Saturday morning.  I've downloaded
and burned the DVD, and I've taken careful inventory of all my local
customizations, so I think that I'm ready to upgrade.  However, I'm
concerned about one thing.  The following web page:

http://www.redhat.com/rhel/moving/

says 

Transitioning your existing Red Hat Enterprise Linux AS/ES/WS
installation to Red Hat Enterprise Linux 5 couldn't be easier. Your
subscription
already entitles you to version 5, and you will be able to access the
appropriate distribution channels when you login to Red Hat Network. Simply
download the new version and install it.

However, if I go to my RHN page and click on "channels" for my server,
there is a menu for "base channel" that currently has, unsurprisingly, 

"Red Hat Enterprise Linux ES (v. 4 for AMD64/Intel EM64T) [no change]"

but there's nothing else on that menu!  I assumed that after I upgraded
the software using the DVD, I would connect to RHN, change my base
subscription to RHEL5 and use up2date to download all the patches. 
However, I can see no way to change my base subscription to RHEL5.  Is
that somehow automatic with the upgrade, or am I missing something?

Thanks,

Scott

--
Scott D. Anderson
Computer Science Department
Wellesley College
[email protected]