That sounds very pollyanna-ish, and assumes US electioneering to be a solid paragon of lawful procedures.
If the Dems want to move the calendar around, they can easily do that, get courts to do that for them, and make it all work until about early September.
I’d make you a steak dinner bet. Rutbaga will be the nominee on the DNC ballot in 2 weeks.
I’ll have Pollyanna sauce on that.