Choosing a CR end date

Hi everyone,

There are a couple of fixes that need to go in (around broken links), but
we're now ready to move to CR. According to Mike[tm] Smith, the most
significant thing we need to do right now is to choose a CR end date.

So, what date do we pick? The 31st March feels a little close given that
the only spec-compliant end-node I'm aware of is geckodriver (and that's
still has the new session stuff and the pointer actions to land) Would
someone from MS, Google, and/or Apple be able to offer some input on a
realistic date we should be targeting?

Many thanks,

Simon