I know I'm late to the discussion
and the link is wiki, but light wasn't around until after inflation
https://upload.wikimedia.org/wikipedia/commons/6/6f/CMB_Timeline300_no_WMAP.jpg
Which would mean that there was no light until the first stars lit 362 million years after inflation and therefore no speed of light. Light is the big boy in measurement terms now but there are 400 million years before it was around and 20 million years when it was openly defied by our wonderfully complex universe.
It seems to me that the universe from big bang to end of inflation existed only as a large bowl of quantum 'soup' that had no respect for Einstein, Maxwell, Lorentz or any one else. Someone getting their minds around what that soup consisted of and it's behaviour is probably not happening in whatever is left of my timeline.