The purpose of this talk is to note a few special consequences of gauging ’’maximal’’ quark‐lepton symmetries such as SO(16), which is the maximal symmetry for a single family of fermions. Within these symmetries, violations forB,LandFare spontaneous rather than explicit. Furthermore these symmetries as a rule permit intermediate mass scales &angupr;(103−106GeV) and (108−1011GeV) filling the so‐called grand plateau between 102and 1015GeV. It has been shown in earlier papers that within these symmetries proton may decay via four alternative models: i.e. proton→one or three leptons or antileptons plus mesons; some of which can coexist. It is now observed that evenn−? oscillations can coexist with (B−L) conserving proton‐decays of the typep→e+&pgr;0etc. without posing any conflict with the cosmological generation of baryon−excess; both these processes can possess measurable strengths so as to be amenable to forthcoming searches. Search for alternative decay modes of proton andn−? oscillations, even as processes in second and third generation experiments, would provide valuable information on the question of intermediate mass‐scales and thereby on the design of grand unification.