I would guess the IPO is undersubscribed and hence the...

I would guess the IPO is undersubscribed and hence the postponement.
Setting the IPO price at $13.06 is above where it has been for the majority of the last 6 months.
When the IPO was announced in June the price dipped down to the $10 range.
Unless there is some sort of surprise announcement in the next day or 2 then I don't see where $US 70 million is going to come pouring in from.
Benitec is small and unknown in the US and was already available for those in the know via BTEBY and BNIKF.
For those buying on the ASX at .95c it is the equivalent of around $14 for BNTC. So the IPO needs to go ahead at $13 and then jump almost 10% to match their buy price. Until the IPO is confirmed I don't know why anyone would be buying at these levels.
If the IPO does go ahead then the ASX will become the follower and the NASDAQ will lead the way.
Last week 4 out of 10 planned NASDAQ IPO's were cancelled or postponed. Seems like it might be a tough time to launch an IPO