  We estimate the energy reservoir available in the deconfinement phase
transition induced collapse of a neutron star to its hybrid star mass twin on
the "third family" branch, using a recent equation of state of dense matter.
The available energy corresponding to the mass-energy difference between
configurations is comparable with energies of the most violent astrophysical
burst processes. An observational outcome of such a dynamical transition might
be fast radio bursts, specifically a recent example of a FRB with a double-peak
structure in its light curve.
