What is the current serialization status of D.Gray-Man?
According to this article dated July 4th, 2015 on Anime News Network (which I believe is a reliable source):


  Jump Square Crown will launch on July 17. The new magazine will publish Katsura Hoshino's D.Gray-man and Yasuhiro Nightow's Blood Blockade Battlefront Back 2 Back. 


So D. Gray-Man is going to be serialized again, but it is going to be serialized as a quarterly manga, so it will be something like 4 chapters a year of about 100 pages each

Edit:- D Gray Man Chapter 219 has been released, 53 pages of content excluding the announcement, Color page etc.