Software update Groups

When you create a new software update group for example, 2014 windows updates. You download it and it will create a Package, you distribute it.  

So next month you download a new round, lets name it, office 2014 updates. You download it create the package distribute it.

So, if o edit the membership of the office 2014 updates, and join it with 2014 windows updates,  what happen with the packages? How SCCM2012 manage this 2 separate packages and the distributions.