Hard question to answer as it depends on the region and what hour of the day.
But for information:
Peak hours start on Thursdays, to Sundays each day having a higher peak than the previous day. (so Sunday would be the highest peak)
Monday and Wednesday are the days we have the least traffic.
Peak hours start around 2-4PM EST for Europe, or 7-10PM EST for NA if that is what you want to avoid.
Hopefully, that makes sense and answers what you need ^^
We don’t share that information anywhere as of right now, and I am not sure if that will be a concern as of right now, but it is at least on our minds now.
Thank you ^^ 
We’ve answered about the slowdown of last week here: A look at the recent service instability if anyone else wants to read it.