The Chattahoochee singer was scheduled to play Bank of New Hampshire Pavilion tomorrow night.

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According to Bank of New Hampshire's Facebook page, Alan will have to sit out tomorrow's show due to an illness. The posting didn't go into further detail, but it must've been sudden. In the message posted Thursday afternoon, apparently trucks and crew were already on their way. As of press time, there isn't a firm date, but the show will be rescheduled as of right now, and fans will be alerted when tickets are available.

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We're obviously hoping for a speedy recovery for the almost 60 year old Jackson. That's right, AJ doesn't look like it, but he'll turn 60 in October. Anyone who has been to his shows knows they're in for a night of wall to wall amashes. From breakthrough hits like Don't Rock The Jukebox, straight through classics like Livin' On Love, he's a guy who can routinely forget to play songs which went to #1. When he plays the rescheduled show, he better NOT leave out latter-day jam Good Time.