In Section 22 in his "Relativity" Einstein denounces the validity of the
principle of constancy of speed of light in the presence of a
gravitational field. This means that, according to the equivalence
principle, as we replace the system experiencing a gravitational field
with an accelerating system, the variable speed of light in the
gravitational field becomes also variable with respect to the observer
in the accelerating system and depends on the speed of the observer (see http://www.wbabin.net/valev/valev3.htm ).
Einstein does consider the aftermaths. He says: "Now we might think that
as a consequence of this, the special theory and with it the whole
theory of relativity would be laid in the dust." Under these
circumstances any ethical scientist would present a thorough argument
convincingly explaining why an observer measuring a variable (e.g.
greater than c) speed of light should still continue to believe in the
theory of relativity. However "Einstein" and "ethics" form an oxymoron.
He just offers a suspicious comparison and leaves it at that.