Thanks for posting in the forums! Please note that we are no longer accepting new apps or games to the Amazon Underground program after May 31, 2017. However, we are accepting version or metadata updates to existing Amazon Underground games, and encourage developers to continue to keep their existing submissions updated for the best end user experience until the program ends in 2019. Please note that if you have an existing Amazon Underground submission in the program, it will need to continue to meet the program's eligibility requirements for participation.
For more information, please see: https://forums.developer.amazon.com/articles/69139/underground-actually-free-program-faq-2017-update.html
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