I can't believe what I'm seeing is the case regarding DFP. Before if you wanted to add an ad slot, all you needed to do was grab the ad slot code, and add its corresponding line to the DFP code in the head section.
NOW, let's say you have two ad units/slots and your code is all deployed, and you want to add a third slot.
You add it, generate the tags, BUT the code is different -- the ad unit identifiers change, so that your previous ads already deployed break.
So, the way I'm seeing this is that every time you ad or modify an add unit, then generate the code a second or third time, you need to change ALL the code, just as you are starting out from scratch.
I searched around, and can't find anything on this. Hoping I'm doing something wrong here, but obviously if you serve adsense/other ads through dfp, it's a huge problem.
If you do that, and regenerate the code, Check to see that you didn't break your previously deployed codes.
Solutions?