When I transitioned in california, the law allowed for a common use name change. This means as long as you don't use your name for illegal purposes, you can call yourself what ever you want. I applied for all my jobs in my new name and never needed to tell an employer about my old name. After surgery I was able to alter my records to my new name. It's a little more complicated now because they run checks on you social security number and they run more employment history checks so at some point in the interview process, your old name may be needed. More or less, you wouldn't need to worry until detail work history or a social security number is required.