https://www.gamespot.com/articles/new-fortnite-jetpack-mode-fly-explosives-available/1100-6460859/

Epic has rolled out a new batch of content for Fortnite: Battle Royale. The v5.10 content update is now available for all platforms (PS4, Xbox One, Nintendo Switch, PC, and iOS), and on top of reintroducing the Guided Missile to the game, it marks the start of a new limited-time game mode: Fly Explosives.

As its name implies, Fly Explosives is a new variation of the limited-time High Explosives event from earlier this year. Only explosive weapons such as Grenades and Rocket Launchers can be found in this mode. Jetpacks also return in Fly Explosives, where they will occasionally spawn as Floor Loot.