Knowing Lim Dall-Young it's neither on hiatus nor ongoing. He always has had an extremely weird sense when it comes to updating and finishing his series.
When I first started reading Freezing it only had 40 chapters or so. I eventually looked at the other series he might have made and he really had and still has a lot of series running simultaneously. I remember that back then outside Freezing and the Legend of Maian he had three other series going and neither of them was updated regularly. Eventually he finished two of these three, however he also started - and finished - yet another series while all these were still running. During the course of all these years there have been added some chapters to the Legend of Maian, so it's not like the series is forgotten, he simply has a really messed up sense of having closure. It's possible suddenly some chapters appear tomorrow, it's possible you don't see any for a whole year. Even the release date of Freezing, his most popular manga, has been often very irregular.
I'm also pretty sure I forgot to mention some of this other series.
Edit: I indeed just remembered yet another series that's still ongoing of his.
