Well Well!!
The first main plot of D-gray man was to find the exorcist that holds the "heart" right?
There some speculation that its either Allen or Lenalee. It holds the power to defeat the noahs?
But somehow it got lost in the middle and focus on different things like the 3rd or the noahs.
Now Allen suppose to hold it as it says at the end of the chapter...
The author is juggling around and I just hope it stay on track like in the past -.-

It doesn't necessarily say Allen holds the Heart. From what it sounded like, the guy (who is probably Lulubell) was saying that the Heart is worried about Allen. (Linalee? Johnny? XD) Though that may just be awkwardness on the part of the translator who was trying to say they were worried about Allen and especially worried about the Heart.

Also, the Heart doesn't have the ability to "defeat the Noahs" (at least, they have never said it does), the point of finding the heart was to protect it because if it's destroyed, then all the other Innocences will be destroyed as well.

At this point I'd say it's definitely not Allen now, and it actually kind of makes Linalee not that possible at the same time...just what I think.

Timcampy is the heart? or at the very least a gate/link to the heart...

I don't think they said that Allen holds the heart, which translation/version did you read?
The heart is worried about Allen because of the state he's in (emotionally more than physically) and who can blame him...lost his master, friends and he was the one responsible for all of this happening even though he didn't wish for any of this....and still, on top of all this is Mana, the one who started this all.

Either way I'm glad the series is moving forward again and answers to questions such as these will be coming soon. There has been too many questions up to this point without much to go on, but things are moving again and that's all that matters.

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so the bookman are actually working for the noah and the earl? and the black order seems to be somewhat evil too. poor allen has hard life lol ready to see the 14th and finally learn the reasons why behind his actions and motives

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The Bookmen are not working for the Earl... They're a neutral party whose purpose is just to observe history and record it. In that scene the Bookman is being threatened to tell everything he knows about the 14th because that Noah with the creepy tongue put some sort of disease/parasite in Lavi and Chaoji.