Since Swap ⇔ Swap is one of my favourite 4-komas out there, I have been snooping around a little. I don't know how reliable these informations are, so take them with a grain of salt.
I still don't know what the gender of the author is (nor do I care about that), so I will refer to him/her as author. Now what I have been doing is basically stalking, but the information I collected is public via the Kirara Time Carat magazine and author's SNS posts. I will not pry further into author's personal life and I would like to ask everyone to respect the author and the situation and not to bother the him/her with further questions. I have learned enough to feel bad looking into it.
So first of all this:
https://imgur.com/a/htGploE
Announcing a sudden hiatus of Swap ⇔ Swap, some other series I don't know about and Hidamari Sketch in the next volume. The second is announcing that Swap ⇔ Swap will end in the next chapter.
My opinion is that this was probably not planned if it's so sudden.
After that I have looked up author's SNS. I will not list the posts, they are still up if anyone wants to see.
Around Christmas time author announced on SNS that the author's son had caught a cold and couldn't post because of the work schedule. After that came a lot of im@s posts and mentions of Comiket goods made by author, depicting a certain im@s character.
The next post is from 6th of February, when author announced the end of Swap ⇔ Swap. In another post author mentioned a health problem and working multiple jobs at the same time and 'various bad things'.
Or maybe the 'jobs/works' are simply referring to independent im@s works, plus taking care of a child and working different jobs could have been taking a toll.
After that author received an original copy of an artwork featuring Haruko and Natsuko from the Kirara Exhibition and was overjoyed. Author even told that he/she will buy this artwork of his/her favorite manga.
Again my opinion is that you wouldn't refer to your favorite work so fondly if you grew tired of it and wanted to end it quickly
In yesterday's post author mentioned that the situation with im@s and Kirara deteriorated and wants to draw Swap ⇔ Swap again. Also mentioned that several posts were deleted.
What I can put together is that the situation is complex, but I can think of some scenarios:
1.: Because of the health problems and working various jobs at the same time the author had to give up drawing for Kirara altogether, which probably doesn't pay well at all.
2.: Because of the health problems, Kirara forced the author to give up the spot in the magazine to fill it by someone who can submit works regularly.
3.: It could be that because of the released im@s goods at comiket, the author stumbled upon legal issues and Kirara just broke up the contract for Swap ⇔ Swap, because they did no want to deal with it.
In any case, my opinions are in italics, and are no facts at all, feel free to refute them. I would like to ask everyone again: please do not bother author with unnecessary questions, because the situation looks complex enough and probably involves personal life issues too. It is already bad enough that we will lose a fun series.