This issue is a shortcut to Grav 1.6 features and progress.
Following features and changes have currently been planned for Grav 1.6.0. The list is not definitive and may change based on changing priorities and ongoing progress:
onShutdown which is not reliable on some setups)It's worth noting that PHP 7.1 hasn't really landed in any of the Linux LTS distributions aside from Ubuntu Bionic, which is still fairly new. Both Debian Stretch and Ubuntu Xenial ship with PHP 7.0, and don't yet have PHP 7.1 available as an option, either as separate packages or via backports. This might change before December, but they might also elect to backport security fixes instead.
Dotdeb also seems to cap out at 7.0, at the moment.
RHEL/CentOS has support for newer PHP versions via SCL, but that too depends on your hosting provider actually supporting it, instead of simply depending on the distribution packages.
Add "Improve Backup functionality" .... Along with "Scheduler" integration, I would like to have some config options to provide more control.
FYI: There is a progress update in my first comment.
@rhukster From a clean installation of 1.6-branch from Git, as well as Admin v1.8.9, here are a few notes from testing on Windows in /admin/config:
bin/grav scheduler --install yields (crontab -l; echo "* * * * * cd C:/Caddy/Grav;C:\Caddy\php\php.exe bin/grav scheduler 1>> /dev/null 2>&1") | crontab - on Windows, it should just return "Create a scheduled task, see learn.getgrav.org/advanced/scheduler" or something to that effectbin/grav scheduler -d, with no actually run jobs, defaults to 0 - yielding "1970-01-01 01:00" for "Last Run"Image 1:

Image 2:

@OleVik You need the 1.9 branch of Admin to go with 1.6 of Grav, the updates are in there.
Is 1.6 compatible with plugins/themes created on 1.5 (or earlier) ?
Yes, everything should be compatible.
Yes, Grav 1.6 should be mostly compatible with Grav 1.5. There are some edge cases, though, which will not work in the new version because of some architectural changes or fixes that have been made, but those should be rare and it was worth of risk to improve the code.
Of course, there may also be bugs, so please test the RC release(s) with your site and report of any problems. :)
Most helpful comment
It's worth noting that PHP 7.1 hasn't really landed in any of the Linux LTS distributions aside from Ubuntu Bionic, which is still fairly new. Both Debian Stretch and Ubuntu Xenial ship with PHP 7.0, and don't yet have PHP 7.1 available as an option, either as separate packages or via backports. This might change before December, but they might also elect to backport security fixes instead.
Dotdeb also seems to cap out at 7.0, at the moment.
RHEL/CentOS has support for newer PHP versions via SCL, but that too depends on your hosting provider actually supporting it, instead of simply depending on the distribution packages.