Here : there is no singularity and there never has been. The gravitational well which was formed by the collapse of the massive star concentrates the mass but the density never becomes infinite. A maximum density is reached and this density is the Planck density. In fact, when the star collapses, it happens in a very short time in the star's own time (but which can be very long for an outside observer) that the quantum gravitational pressure (this is how Rovelli calls it) opposes the collapse, which produces a violent rebound. As I said, this would take place in a very short time in the proper time of the star, but as this phenomenon takes place in a very deep gravitational well, beyond the horizon of events, where time is therefore extremely dilated, for the outside observers that we are, this duration seems to us to last (sic) very long, millions or billions of years ...
As the effects of quantum gravity are governed by the energy density and not the size of an object, Rovelli specifies that the "star", which with Francesca Vidotto they call a Planck star (Planck Star) can have anything made to have a dimension greater than the length of Planck.
What is more, as black holes evaporate by Hawking radiation, Italian theorists show that the Planck star, which contains all the information of the black hole, ends up losing a third of its mass by Hawking radiation, leaving a macroscopic residue, with a horizon which then disappears. At this point, the quantum gravitational pressure can then dislocate the residue and the information stored in the black hole escape to infinity.
http://www.ca-se-passe-la-haut.fr/2014/02/etoiles-de-planck-la-fin-des-trous-noirs.html
To summarize: in current theory, based on general relativity *, a black hole will create a gravitational well of infinite depth.
In the theory of quantum gravity, this same well will have a gigantic, but not infinite, depth.
In this case, the collapse does not last, once the maximum threshold is reached, a rebound is created, which means that after a given time the Planck star will stop being dark and become a powerful source of light.
* The infinite density described by relativity is to be compared with the incompatibility between theory of relativity and quantum physics.
The new theory, known as quantum gravity theory, takes into account advances in subatomic physics and allows calculations to be made that are more related to physical reality.
"Engineering is sometimes about knowing when to stop" Charles De Gaulle.
