[ Did you miss a decimal point? 4.7 or 47 billion years? ]
Why not?.. either number is just an estimate..
4.7 or 47 or 477 billion is a linear assessment..
Time may not be lineal..
Non-linear time is a different issue. And you may well be right about that.
The question is one of measurement (using the speed of light as the standard of measurement), and possibly even the viability of the currently popular Big Bang Theory.