Assuming you are from the UK server:

Matsuri starts at 19:00 hrs while Nine tails starts at 20:20, so that's already an 1 hour 20 min window to do Matsuri.

If it took you 40 min to kill 9 tails (with 3 strong players in our server and 30M+ HP it takes us less than 20 so i'm surprised at how long it takes for you), you would en at 21:00 hrs, which leaves you 1 more hour to finish Matsuri. them

While the new format for 9 tails has its problems, complaining about how long it takes to kill it is not a good argument. In any case, the chances Oasis will roll back an update is slim to none, specially one which does not bother the majority of the playerbase.