Ann: Outcome of Scheme Consideration Elections and Scale Back, page-2

Consideration to be provided for Share Elections
iiNet Shareholders who made a valid Share Election will receive, for each iiNet Share held continuously from the Election Date until the Record Date (currently expected to be 5:00pm (WST) on Monday, 31 August 2015):
 0.5533 New TPG Shares;
 $3.77 in cash; and
 a Discretionary Special Dividend of up to $0.75 per iiNet Share (if declared) in cash and top-up cash consideration for the difference between the amount of the Discretionary Special Dividend declared (if any) and $0.75.


I need help here. So, 1000 IIN shares equals:

553 New TPG Shares;

$3770 in cash; and

What does the last bit mean and how much will/could it be?