Some notes on The Plan, from IRC just now:
<dlr> kfogel: I only kinda started on the core library patch for
issue #2961. I've attached the tiny patch to the issue.
<kfogel> dlr: looking
<dlr> I'm guessing that we need to add some actual upgrade logic as
<kfogel> dlr: I've still been toying with the idea of "on-demand
bump", that is, only when one of the nasty features is used.
<kfogel> But with your script, maybe it's okay to just upgrade
<kfogel> (the on-demand strategy was controversial even without your
<kfogel> One thing I want to do is make sure the script is referenced
in any version-mismatch error message between 8 and 9.
<kfogel> too late for that, since it's a 1.4 client that would get the
<kfogel> So, we should make a generic page for such notices now, and
have 1.5 refer to the page, in case we have *future* downgrade
<kfogel> I'll transcribe this all into the issue.
<dlr> sounds good