My 2 to 3 weeks included footing excavation, re-pour, stack ‘em and grout ‘em.
Excavation might takes couple days because I assume they’re retaining.
But with the heavy equipment they’re using and have parked on site, should be fast.
And they’re bringing in dirt so back fill should easy.
Especially if they’re knocking it down anyway.
I don’t know about the engineering of the thing. They’ll probably require a geotechnical stamp for a wall because that’s how the City rolls.
Drck would know better though.

Or are they that dumb that they’re gonna leave the compromised wall standing and just sync up rifle and pistol sides ?
And it’s a later project, closure.