SEE ALSO: U-KISS are dashing in solo teaser photos for mini-album 'Moments'

But no worries as this doesn't mean he's leaving the group, he'll just be taking a temporary leave of absence as he resumes his studies to maintain his enrollment at the school like he has done previously.

NH Media wrote on U-KISS' official website:

Hello. It's NH Media.
We thank the fans who are always supporting U-KISS.
We are making an announcement about the important matter of AJ's study overseas in the States.
AJ, who is currently enrolled in Columbia University, will be returning to the States starting January 2014 to continue his studies. 
We know that many of you will be surprised by the sudden announcement ahead of their comeback.
It does not mean that he will leave U-KISS, and just like how he had a short hiatus for his studies last year, [AJ] plans to return to promote with U-KISS after completing his studies.
Their scheduled activities within this year for their 8th mini album, which will begin soon, will go on as planned with no changes.
We apologize for sharing this news ahead of the promotions for their 8th mini album. There will be no changes to the activities for their mini 8th album that starts this week, so please give them your interest and support.

Thank you.

So it seems KissMe's will have to treasure the next few months until 2014 as AJ will be absent from activities for at least a portion of next year.

The boys will be releasing 'Moments' on the 31st, so give them your support!

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