Hello and welcome! There is an Xcel focused group on this board that you may wish to join. Someone asked a similar question on the Xcel board just recently and the answers were typically around 6 hours on the low end and some gyms doing 12+ on the high end. It really depends on the gym, their philosophy towards Xcel, if Xcel is a larger/more competitive program in your state.
Thanks for the replies -- it's helpful to have a sense of the range. My DD recently started up in an advanced rec class in a new gym after some time away from gymnastics, and the coaches asked if she's interested in competing in their Xcel program. She is interested but not 100% sure just yet, and she's also been diving so there's that to consider.
Anyway I am going to ask the coaches for more info so I wanted to have a ballpark of hours.