Current devel version will be numbered 5.5.0 and it is planned to be released in the 2021.
Previous devel, current stable, version was 5.4.x (released during the summer of 2020), see what was new in that release at:
This is a draft of new features added in devel version, manually updated, thus not always synchronized with what is new in source code repository.
* RPC reload limit controlled via reload_delta module parameter