It's not your fault, nor is it SE's fault. The blame lies with companies such as TATA, Level3, etc. Basically your connection is being severely bottle-necked at peak times by these companies, your ISP routes your connection through them to make it to Montreal.

From what I understand (somebody else can explain more, this isn't my profession), the reason the problem is more prevalent right after updates is due to the fact that every time the servers are rebooted, their connection is reset and usually re-pathed. More often then not this settles out as time goes on and the problem subsides for most people...until the next patch.