Elizabeth,
Thanks for your question!
Now I cannot speak to any impending partnership between Disney and Fitbit (because nobody is telling me!), but I may have some workaround solutions for you. I am not a Fitbit guy, but I am always sporting my Apple Watch, and that creates the same kinds of considerations. I
answered a similar question a while back on this very concept.
First of all, the
ShopDisney online store has a
MagicBand section that has lots of different bands you can purchase. But also there you will find a lanyard 'medal' where you can remove the core 'puck' from the middle of the MagicBand and put in this medal that can then be clipped to a lanyard, or a belt loop or similar location. This is just one of a few similar items they have in the stores at the resorts and parks down at Walt Disney World.
But a solution you might like even more is what I do. There are a lot of people on Etsy that have created puck holders that will slide on to your Apple Watch, Fitbit, or other watch band. Again, you would unscrew the puck from the band, nestle it into the bracket, and then slide that on to your watch band. The one I bought was VERY secure, and it resulted in me having only the one watch band, with both my watch and my MagicBand pass together. You could do this with a Fitbit just as I did with my Apple Watch.
Your steps (and there will be a lot of them!) will be preserved!
Have a Magical Vacation!Doug