Being authentic means trusting your gut and moving ahead. It means that many times, your questions will be more important than your answers. On a personal level, it's where deeper truths are discovered.
When I ran into my own life crisis around age 49 -- a divorce and losing my job for the first time ever -- I took the time to sit and consider what I wanted more of in life. I decided I wanted more fun and meaning, but I did not realize at the time how much courage these goals would require.
Whether it's reinvention or re-assessing your skills, adaptation is a fact of life. If the changes in your field call for new skills, then go out there and learn them. All that is holding your back is your belief that it is too hard or you're too old.
There is always an open door to reinventing yourself. If we move with the events of life, holding on to our memories but letting go of the past, and plan for the future but meet openly whatever arises, we discover that our life is more vibrant and free than anything we imagined.