There is a fifth “Release Candidate” of the popular WSJT-X software by the developer K1JT, Joe Taylor: WSJT-X 2.0-RC5.  It is available NOW for download.  

WSJT-X 2.0 is a major update – most important are the new FT8 protocols – these protocols now convey 77-bit information payloads compared with the older 75bit along with cyclic redundancy checks (CRCs) being extended from 12 bits to 14 bits.   This is very exciting because it enables new FT8 message formats and the new WSJT-X 2.0 was built with contesting in mind.  More details on these changes can be found in the quick-start guide for WSJT-X 2.0  Also important – the new modes are NOT backward compatible.  This means you may want to install the RC5 in a different directory if you want to keep the older 1.9X version.   After Dec 10, 2018 WSJT-X 2.0 will be General Available (GA) (no longer considered “beta”) and ALL operators are STRONGLY encouraged to update/migrate to the new releases – you will NOT be able to exchange QSO between the older formats and the new 2.0.  

What better way to try out the new FT8 modes with a contest – check out the FT8 Round up contest Dec 1-2, 2018 – details here at this link: https://www.rttycontesting.com/ft8-roundup/  Be sure to review the contest rules for power levels, times etc.  There are more details on this ARRL post: http://www.arrl.org/news/new-wsjt-x-2-0-rc5-beta-version-now-available-first-serious-ft8-contest-this-weekend