As of nowish, xenial has entered the Final Freeze period in preparation
for the final release of Ubuntu 16.04 LTS next week.

The current uploads in the queue will be reviewed and either accepted
or rejected as appropriate by pre-freeze standards, but anything from
here on should fit two broad categories:

1) Release critical bugs that affect ISOs, installers, or otherwise
can't be fixed easily post-release.

2) Bug fixes that would be suitable for post-release SRUs, which we
may choose to accept, reject, or shunt to -updates for 0-day SRUs
on a case-by-base basis.

For unseeded packages that aren't on any media or in any supported
sets, it's still more or less a free-for-all, but do take care not to
upload changes that you can't readily validate before release. That
is, ask yourself if the current state is "good enough", compared to
the burden of trying to fix all the bugs you might accidentally be
introducing with your shiny new upload.

We will shut down cronjobs and spin some RC images late Friday or early
Saturday once the archive and proposed-migration have settled a bit,
and we expect everyone with a vested interest in a flavour (or two) and
a few spare hours here and there to get to testing to make sure we have
another uneventful release next week. Last minute panic is never fun.

On behalf of the Ubuntu Release Team,

... Adam Conrad