For matsuri, it usually depends on when you are planning to do it. People that have killer lineups don't care when to do but based on my observations, they tend to do it right from the beginning or after nine tails. I usually start doing matsuri 30 mins after it started or 1 hour before it ends since by then you'll probably increase your chances of not meeting someone stronger than you as they have probably finished already. The downside of doing it before matsuri ending is the lack of players in the queue.