Dena bank has replied just another RTI sent by an IBPS PO aspirant. In their reply Dena bank made clear that :-
1) There are 75 unfilled vacancies, which made clear that there will be second allotment for sure.
2) They already communicated with IBPS on 13 August. Few banks such as Corporate bank, delayed the whole process. That's why second allotment is delayed.