I found the assistance at http://support.microsoft.com/kb/273028 very helpful. I was able to use it to update my date footer, running it for each sheet without tediously having to go into the page setup for each one. for multiple sheets very quickly. But for my header, it does not work because it changes the entire center header, which is different for each sheet. Specifically, my center header is currently Q3 2013 XXXX, where XXXX is different for each sheet. I would like to change it to Q4 2013 XXXX, simply replacing Q3 with Q4, without having to tediously go o the page setup for each tab.
Thanks!