Battle at Junton

(SPOILER)In Crisis Core, i've just got to the part where Junton is attacked by Genesis Copies (in Chapter 7). I was just wondering if, at the same time, the original AVALANGE are also attacking (as depicted in Before Crisis). Is this correct, or are they two totally seperate events?

thanks for the spoiler alert

I threw some spoiler tags around the text. Please try to keep spoilers marked in the future.

Sorry! I forgot that not many people have played this game yet.

But can someone answer my query, please.