What is the approximate timescale for the core implosion leading to a supernova once silicon burning ceases?

Answer

Mere seconds

The catastrophic implosion of the iron core into a proto-neutron star occurs on a timescale of mere seconds once the outward radiation pressure ceases.

What is the approximate timescale for the core implosion leading to a supernova once silicon burning ceases?
astronomyBeetlejuicestarsupernova