Hi again,
Famous last words:
These [7.8.5 and 7.9.0] will probably be the final cylc-7 releases.
Cylc-7.8.6 and Cylc-7.9.1 are now available to be downloaded .
Cylc-7.8.6 has two more important bug fixes on top of 7.8.5. One prevents automatic cycle point format conversion when using cylc suite-state or the suite_state xtrigger, if the target suite uses the default format but the downstream command or suite does not; the other can (depending) cause a lot of spurious warnings to be logged at restart, for large long-running workflows.
Cylc-7.9.1 is the same as 7.8.6 except that the bundled Jinja2 version has been upgraded to 2.11.1, which allows us to report the right line number for all Jinja2 errors.
Cylc-7.9.x requires Python 2.7.
Cylc-7.8.x works with Python 2.6 or 2.7.
If you are not stuck with a legacy Python 2.6 system you should go straight to Cylc-7.9.1.
Details:
These will probably be the final cylc-7 releases. 
A new preview release of Cylc 8 (Python 3 based, with a web UI) will be announced soon.
Hilary