I got this the other day when getting some linux isos for 24 hours. It clearly shows a slowdown at night. All transfers were from a premium news provider and as you can see it was perfect until around 6PM.
I see this with websites as well, I cannot watch videos on giantbomb.com as it is too slow, I have to download them.
I'm assuming it is a capacity issue either on rogers or teksavvy but I'm not too worried as I'm getting my money's worth and my transfers aren't critical
I'm in the Merivale/Hunt Club area.