I don't think that motivation comes into play at all. They can't just be shifting assets under mgmt (AUM) from, say, RCP Advisors 3 back to RCP 1. Biohunter already showed us from his DD on RCP that each segment of RCP Advisors has AUM dating from certain time periods (e.g., RCP 1's AUM is for the time period before 2011).
I think its more likely that they didn't want to bite off more than they could chew. Why rush things? Better to do it methodically than risk making some silly mistake. Besides RCP has already almost doubled the purchase price of their shares. Maybe they will get another big jump when the second transaction is finalized and announced!!