Great idea. People who want to be in that first wave right now have to sacrifice things like being able to actually read the story, which in a game where the devs want you to read the story is a shame. They have to rush around doing everything as fast as possible to try and be ready. People with work commitments and kids and such are just not able to take a day off to speedclear everything to be ready for it, excluding them from it not because of skill, but because of adulting.
Setting it back a week gives everyone a week to go through all that stuff and be ready, and puts everyone on a more or less equal footing for the actual race to start. As mentioned, they already do this in the first tier, by what, 4 weeks? A single week wouldn't hurt anyone. As a bonus, instead of having the clear race mixed in with attention on everything else, it would be the community focus on week 2. That gives the streamers and such a week to focus on all the other new stuff, and as soon as interest in that is waning? Boom, savage race!
It's a win all around, really.