When will Steam allow download?

[Wynthorpe]

Here is what some one on the Steam forums has put -

Short answer: timezones

It unlocks simultaneously for the "international" release region.

For me (Australia), it unlocks at ~5am on the 1st of April, at the same moment it unlocks for you.

It unlocks at midnight somewhere.

That doesnt make sense really, release is the 31st which is 12:01amGMT, if its to coincide with a International release that would be GMT+18 hours.