Fortnite received a client patch on Friday, May 24th to address issues with Battle Royale Replays and Save the World localization:
We're releasing a client patch tomorrow, at 8am ET(1200UTC) to address issues with Battle Royale Replays and Save the World localization. There will be no downtime for this update. ??— Fortnite (@FortniteGame) May 23, 2019
There is no new content added as a result of the patch, nor any downtime - once you have it, you can begin playing.
Get help on the latest Fortnite Challenges, including catching the Flying Disc Toy and oversized phone, big piano and giant Dancing Fish Trophy locations. There are also the latest Read what's last been added with Fortnite patch notes, daily Fortnite Fortbyte locations to discover and weekly Utopia Battle Star locations. And, for a limited time only, there's Fortnite Two Food Trucks locations as part of the latest LTM too.
Source : https://www.eurogamer.net/articles/2019-05-24-fortnite-patch-notes-6003234