OSCAR version 19 has been in beta since May of 2019. Developers have declared it stable and ready for production. The reccomended installation version is oscar_emr19-21~1021.deb.
Work is now proceeding for features that were not ready in May and were “frozen out” while work concentrated on making OSCAR 19 stable and fast. These features are scheduled for a minor point release 19.1 later in 2020.