Madonna hadn't planned on releasing her 13th album, Rebel Heart, until spring 2015. But leakers had other plans for the Queen of Pop's follow-up to 2012's MDNA, unleashing early mixes of 13 tracks onto the Internet this week. In response, Madonna has put six official versions of the songs up for sale on iTunes and other digital music retailers, effective immediately. More music will be available February 9th, and the full album will be released the first week of March via Interscope."I was hoping to release my new single 'Living for Love' on Valentine's Day with the rest of the album coming in the spring," she said in a statement. "I would prefer my fans to hear completed versions of some of the songs instead of the incomplete tracks that are circulating. Please consider these six songs as an early Christmas gift."Tracks available immediately include throwback house anthem "Living for Love," the ominous "Devil Pray," the lush "Ghosttown," reggae-tinged jam "Unapologetic Bitch," dark "Illuminati" and the Nicki Minaj-featuring "Bitch I'm Madonna." Producers on the tracks include Diplo, Kanye West, Billboard, Dahi, Blood Diamonds and Madonna, herself. Fans can nab the songs as part of an album pre-order or buy them individually a la carte. In July, Diplo — who produced a good portion of the album's tracks — promised the upcoming songs would be "crazy-sounding." "We really pushed the envelope with some of the stuff we were doing," he said, adding Madonna was "up for anything." "I love when an artist gives a producer the confidence he needs to work with them, and Madonna was very open-minded to my ideas… she was down from day one."