Is there any clarification from the publisher/author of Hunter x Hunter regarding the quality of chapters 335 to 338? Why do Hunter x Hunter's chapters between 334-338 look this bad?

I know that Togashi had several illnesses, but is the illness that he had getting worst at those chapter? (I didn't resize the image so everyone could see the picture very clearly at the first glance).

Has Shueisha ever made a clarification regarding those chapters?

I have the physical books/compendium version of Hunter x Hunter that have relevant chapters on it (chapter 335-338 are included in vol 32 of HxH). But the art is still the same (my physical books of HxH are translated to Indonesian language and it's published through legal sources). 

It happened in the 13th Hunter Chairman Election Arc, started on chapter 334. why the art suddenly/constantly changed?

Page 19, chapter 334



The audience looks are not drawn well, it looks like that scene was still a draft.

In chapter 335, it looks worse than chapter 334.

Page 7, chapter 335



And worse in chapter 336 (it looks like a rough sketch, look at Killua's hair and body, Nanika's inked hair, also the bench....)

Page 12, chapter 336



The worst in chapter 337 (What's wrong with you Kaito... and also the background... just what... )

Page 12, chapter 337



Well, chapter 337 is the worst that I have observed so far... They started to change the art frequently starting from chapter 338, but I would say, it's still bad.

Page 12, chapter 338



and finally, in chapter 340, we can have the fine art from Togashi.

Page 17, chapter 340
(expansion to my comment above, which would have been an answer if I could have found the image below)
I said:


  Are your images from the weekly manga or the compendium volumes? When time pressure hits, Togashi's art will tend to suffer, as he does what he can to make delivery of his weekly art. But when the HxH volume is published, he tends to clean it up so that it looks a lot more like his usual artwork.  – RichF 5 hours ago


I can't identify the page, chapter, or volume, but here is an example image I built to answer a completely unrelated question (What defines the art-style of Japanese manga?):



On the left is Togashi's original page as it appeared in its weekly form.  On the right is his final version of the page which appeared in the associated volume.

Based on Gagantous' reply to my comment, apparently Togashi didn't always clean up sloppy weekly pages for the follow-up volume.  Maybe for the volume used in the Question to show us examples, Togashi's health (and/or deadline pressure) didn't allow for the cleanup.