Nintendo Switch Online subscription not needed for Fortnite, it seems
Nintendo+Switch+Fortnite+Special+Edition+Pack for sale online | eBay
Fortnite - Nintendo Switch - Games - Nintendo
Fortnite On Switch Won't Require Subscription For Online Play - Lowyat.NET
The double helix should honestly be for people who buy Nintendo switch online instead of a switch bundle. It would get more people to buy the service. : r/FortNiteBR