As you may recall, software internals consultant Jonathan Levin recently released LiberTV, a jailbreak tool for tvOS 9.1-10.1.
Based on Luca Todesco and Marco Grassi's work which brought us the Yalu jailbreaks for iOS 10.0-10.2, Levin's original work covered the equivalent tvOS firmwares, up to a maximum of tvOS 10.1. However, Levin may be able to go one better, based on a tweet posted today.