Easier for DNC approved candidate to win the primaries. With the traditional calendar, somebody like Bernie Sanders have a shot and DNC is not going to want that.
Exactly.
After Jimmy "Step N' Fetch It" Clyburn's tour-de-force performance in 2020, the national DNC vote fraud machine realized that it was wasting money that could create general election "ballots" on its fake "primaries".
This way, the "Power By Any Means Necessary" Party cuts directly to the chase, and lets The "It's Like Taking Candy From A STUPID Baby" Party burn all its money and energy on a long primary season.