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We are delighted to announce the launch of not one, but two Binance Futures Testnet Platforms to better serve our users! This gives you the freedom to explore each product and its offerings ahead of the official Binance Futures launch. A total of 10,000 BNB will be given away to users who participate in testing both Futures Testnet Platforms. At the end of the competition period, the mainnet version of the platform with the most votes will provide a 50% trading fee discount to its testnet voters for a full month.

Competition Period: 2019/09/03 00:00 AM - 2019/09/08 00:00 AM (UTC)

https://www.binance.com/en/support/articles/360032888452

So Binance has created two stand alone versions of their future trading platforms, and obviously they wanted their customers to select which one they like best here. There is "Future A" and "Future B" scenario here and the winners getting 10,000 BNB.