Trust me, $300M+ total is locked already. MU had only 11 days before getting killed by DM2, Grown Ups 2, Turbo. IO has 20 days. Also, Cars 1 in its 2nd Monday had a 65% drop Sunday to Monday while Up dropped 67% Sunday to Monday.
Of course, IO will stabilize this weekend. Its only competition is Max, but the best I can see for it is $11M OW while Ted 2 will likely open under $50M.