I just looked at my stats to find my spikes, since I upload twice a week. Although I upload Sun/Wed, I seem to get more hits on Wednesday than on Sunday. The largest spikes are on Wednesdays just from last month. I do get spikes on Sundays when I update also from the readers. I'm not too sure why it'll spike so high at the middle of the week. I'm also pretty sure I have a binge reader that goes away and comes back to binge.
My other stories update almost daily, or just have 5-10 views on the scale and aren't really helpful.
Overall my stats aren't likely helpful to make an informed decision since 1 it's a novel and 2 it has a low number of readers, so it's stats are baby stats.
I do notice that this matches my pattern from dA of when I apparently submit the most amount of chapters - which is usually a Tuesday. Funny how that coincides with scheduled updates and their reading numbers.