Turns out that according to the game files for Fortnite the jetpack will act like the jump pack from Call Of Duty Advanced Warfare. You will use it then it will have to recharge. As well it will only be coming in a limited time mode called "Jump Higher" according to the source code. This might be good for Fortnite due to the fact that the jetpack would change the game in such a drastic way that not everyone would be ok with it, just imagine a sniper flying above you. In my opinion the next new type of movement device that they should add would be vehicles, it is a missing feature of Fortnite that I hope comes in the near future.
