A recent understanding on how quantum effects may affect black-hole evolution opens new scenarios for dark matter, in connection with the presence of black holes in the very early universe. Quantum fluctuations of the geometry allow for black holes to decay into white holes via a tunnelling. This process yields to an explosion and possibly to a long remnant phase, that cures the information paradox. Primordial black holes undergoing this evolution constitute a peculiar kind of decaying dark matter, whose lifetime depends on their mass M and can be as short as M^2. As smaller black holes explodes earlier, the observed wavelength of the corresponding astrophysical signal scales with the redshift following a unique flattened wavelength-distance function, leaving a signature also in the resulting diffuse emission. I discuss the different emission channels that can be expected from the explosion (sub-millimetre, radio, TeV) and their detection challenges. I conclude presenting the first insights on the cosmological constraints, concerning both the explosive and the subsequent remnant phase.