Oh, of course there’s a catch. Ain’t that always the case? To get access to Battlefield Hardline before anyone else you’ll have to be a member of the EA Access service. It’s also not the full game but merely a trial. In the past your progress in the trial version would be carried over to the full game, once you purchase it. The official Battlefield Twitter account confirmed this recently:
@MaximumXtreme Yes, you will be able to get early access to Battlefield Hardline through EA Access.
— Battlefield (@Battlefield) January 19, 2015
No date was confirmed just yet and just how long the trial will last, generally you have several hours to test things out. Battlefield Hardline launches on 17 March for PC, PS4 and Xbox One.