reload: final cycle point cannot be changed after restart

[oliver-sanders]

Changes to the final cycle point don't get applied by cylc reload if the suite was run using cylc restart.

Example

[scheduling]
    initial cycle point = 2000
    final cycle point = 2010
    [[dependencies]]
        [[[P1Y]]]
            graph = foo[-P1Y] => foo

Normally changes to the final cycle point get applied by reload:

$ cylc run suite
# running to stop at 2010

$ sed -i 's/2010/2020/' suite.rc
$ cylc reload suite
# running to stop at 2020

However, if the suite was restarted rather than cold started nothing happens:

$ cylc restart suite
# running to stop at 2020

$ sed -i 's/2020/2030/' suite.rc
$ cylc reload suite
# running to stop at 2020

[matthewrmshin]

Most likely overridden by the stored original.

[oliver-sanders]

See also #2799 which may supersede this.