https://www.gamespot.com/articles/fortnite-new-items-added-ahead-of-season-6/1100-6461809/

We're in the waning days of Fortnite Season 5, but developer Epic still has some new content in store for the popular battle royale game before Season 6 officially arrives. We've gotten our first glimpse at one upcoming item courtesy of Fortnite's in-game news feed, and it looks like it could shake the game up fairly dramatically. [Update: As teased, the Port-a-Fortress has arrived in Fortnite as part of the 5.41 update, along with a new item for Playground and another limited-time mode, Soaring Solos.]

A listing has appeared in Fortnite's News section for an item called the Port-a-Fortress. According to the feed, the item is "coming soon" to the game, presumably as part of this week's update. Based on its name, it sounds like an enhanced version of the Port-a-Fort, a portable item introduced earlier this spring that can spawn a fort a few seconds after being thrown.