At the moment of posting this, the SEDE homepage says it has been updated one hour ago:
However, when I try to execute a cross-site database query, it runs into an error:
According to Taryn's comment,
The job is scheduled to start at 3am UTC and runs for about 5 hours, so probably just some contention.
So that means I have to wait for an hour or so; no problem, but the 'Data updated' message is wrong right now (bug). Ideally (feature-request), it should show that a refresh is taking place right now.