Both editions collect the core books in the series plus some extras. To avoid confusion, I disable the old versions.
If you purchased most of the respective series, you had the new editions added to your account. If not, you'll have to buy the new edition. However, the sale price of consolidated editions if lower than it would have been to buy the whole series.
Check out the WWII homepage for more details on upcoming WWII d20 modern ebooks.
Looking to get the complete set? We have two bundles to help you get these modern books on the cheap. The Blood and Guts 2 Bundle include every book in the line and the Blood and Guts 2 vehicles include just the 3 vehicle books.