Romanenko, A.S. JACoW Publishing Geneva, Switzerland It is currently believed in the field of SRF that the limit of the achievable accelerating gradients is set by the DC superheating field value, which guides most of the theoretical and experimental studies in this direction. However, it was recently proposed* that another mechanism is currently enabling both the existing SRF cavities with the quench field in excess of niobium Hc1, and providing the path forward to higher gradients, namely the vortex nucleation time slower than the rf period. If true, differently from currently pursued higher DC Hsh materials (e.g. Nb3Sn, MgB2 etc) or multi-layered structures, the new proposed directions are doping of the top niobium surface with special types of inelastic electron-phonon scattering "slowing down" impurities, or coating with thin layers of LOW (and not high) Tc superconductors. Both experimental and theoretical progress at Fermilab in this new area will be presented.