I'm getting this hair color (silver ombre) with streaks of teal mixed in! I'm very excited for it.

What I am wondering now is should I bleach my hair first before going in? I currently have red hair and that is the hardest color to get out. I have two boxes of bleach. I don't want to spend all day in the salon bleaching my hair or worse, have to be told I have to come back to finish dying it because I want my hair done for my first day back at work.