  We argue that non-supersymmetric SO(10) models based on a renormalizable
Higgs sector in which spontaneous symmetry breaking is triggered by the VEVs of
a 45-dimensional adjoint and a 126-dimensional tensor representations can
provide a potentially realistic yet relatively simple framework for a future
robust estimate of the proton lifetime. Following closely the work
Phys.Rev.D85, 095014 (2012), arXiv: 1202.0807 [hep-ph] we comment on the gauge
unification constraints on the B-L breaking scale and show that there are
several regions in the parameter space of the minimal model where the seesaw
scale in the phenomenologically favoured ballpark of around 10^13-14 GeV is
consistently supported.
