Posting it here in case you missed the announcement from the release team:
Due to the ongoing evolution of the fixes for the recently announced
Meltdown and Spectre security vulnerabilities , we are delaying the
16.04.4 point release, originally scheduled for the week of February
15. We intend that, when it is released, 16.04.4 will include kernels
which mitigate these severe vulnerabilities. We also recognize that,
because updates for these security vulnerabilities are currently
monopolizing the SRU queue for kernels, there is no opportunity for
any other point-release-critical fixes to be included, and we need to
allow the dust to settle a bit before putting the finishing touches on
the point release.
We are currently unable to set a new firm date for the release, but we
do not expect the schedule to slip more than a few weeks.
We will send a follow-up email once more is known.
On behalf of the Ubuntu Release Team,