The auction begins at 12.00 GMT and normally takes 2-3 hours to complete
There’s also a decent size option expiry at 0.7710 which may come into play around that time too
As Eamonn pointed out here the last auction produced a price gain +2.4% against the trend for much of last year so this one will be keenly awaited
GDT auctions 2014
NZDUSD currently 0.7738 with offers around 0.7750 capping the earlier rally
More details at the GDT site here