With the typical timeline, normal raids are released 2 weeks after the expansion, and the savage tier is released 2 weeks after normal raids. This means raid comes out December 21st and if you don't clear by Friday night then you're raiding for Christmas or risking not clearing week 1. Delaying savage by 1 week is also not a solution as it then collides with when JP players spend time with family. So either it is delayed even further, or released earlier. Between the 2 choices, I personally think 3 weeks after the expansion is enough time for the players who want to raid day 1 or week 1 to complete MSQ, while still giving enough time for the hardcore raiders to complete it before Christmas.