Leakers inform that, according to the current Epic Games scheme, on April 27 there will probably be significant changes on the map.
All map changes in Season 6 were generally only for the barricades. These have not changed much at the moment. This thread may develop in the coming week, i.e. with the update 16.20.
Meanwhile, leakers inform that on April 27, slightly larger news should be expected, including the football stadium.
April 27 and Neymar in Fortnite
It all has to do with Neymar. He is due to become available on April 27th. Since it will be a really loud skin and collaboration, you can expect major and minor changes to the island.
Unconfirmed information indicates typical football challenges that are to revolve around the stadium. How will it look like and details are not yet known, but it can be viewed as a mini-event. It is very possible that we will find out more about April 27 in patch 16.20, but there is also a chance that we will have to wait until 4:30 PM.