Yeah, this happens from time to time, esprcially around the fall/midwinter/early spring seasons.
Since a lot of the readers on Webtoons are on the younger side, there is school to think about (elementary, high school, college, etc.), if not other responsibilities.
I wouldn't sweat it. A lot of sites will have moments of inactivity, as @Daknight pointed out.
It's just something to adapt our schedules to.