  A fully QED/relativistic theory of light pressure of CMB radiation and
Fokker-Planck equation for electron distribution combined with cosmologic
relation for CMB temperature, T, yields analytic results for the evolution of
the distribution over large span of time and energies. A strong imprint of CMB
on electrons transpires via formation of "frozen non-equilibrium" state of
electrons in current epoch, and possible existence of cutoff and narrow
spectral lines as remnants of high-T sources.
