[CentOS] Question about updates again

Presumably, the CentOS 4.3 update is not far away. I have CentOS on several servers now and am doing automatic updates. What can I excpect when the actual update gets pushed? Is there an inclrease in the number of patches? Does it happen all in one day? And if so, how much notice do I have?

Although I asked on the list a while back, I got some answers that implied said that at update time, bug fix patches are released and at other times only security patches. But I also got a couple of answers that implied that the quarterly update was just a CD that brought the distro up to date with the already issued patches. Sorry to keep beating on this issue, but I want to avoid surprises.

Thanks, Steve