We'll be releasing an update for Switch players tonight at 11 PM ET (03:00 GMT) to fix a bug with nameplates in our Playground mode.— Fortnite (@FortniteGame) August 1, 2018
There will be no downtime but you may need to restart your game to catch the update.
I haven't given Playground mode a try yet. I should probably do that before the mode disappears again. Hop on, grab this fix, and give it a go!