Sorry, but you really should have proof read your post. You have written "the NEW Prepar3D V.2", and then later on wrote "to work in that PREPAR3D V2.4", so I have to assume that you mean Prepar3D v4.2.
The answer: You will have to buy them all again for P3D v4.x.

So far, only the 757 Captan III, and 737 Captain are available for P3D v4, and I haven't tested the 737 in v4.2 yet, so I'll go and do it now.