I searched the archives of several websites, I now recall exactly how it went down.
The simple truth was that it was neither played nor leaked until September 23rd. It was first played and leaked on the same day.
The Spanish DJ version was from U2Valencia, which was the first full version leaked however, it was not the first time it was played, it was merely the first time somebody had recorded it.
Who played it first? Belgian, German and Spanish radio all had reports before both Dave Fanning and Triple J.
After reading all that, I remember it happening exactly that way.
There was however one 30 second promo clip from Australian radio on the 21st. I still have that version and the U2Valencia version.