my guesses on this last subject:
CP9 round will end in EL. After that Impel Down will be somewhat like Drum, not really a third round. Maybe a crew member (Soge?Zoro?) could be captured during the EL incident and sent to Impel Down and the crew goes there to rescue him/her/it. During ImpelDown they will find a way to pass unoticed thru WG HQ…. don't know how.
Of all the things in this last ARC the one that makes me more intriguied (sp?) is how da hell is pirates that make a fuss like that in EL going to pass the HQ? no idea... i've just written and deleted three ideas -_-