webstats-tb.html graph too eager to include today's stats

Today the graphs on the https://metrics.torproject.org/webstats-tb.html have collapsed -- all four of the graphs fall off abruptly at the most recent data point.

I checked with weasel and it looks like the data should be getting from the webservers to metrics, or at least nothing has changed there.

So my next guess is that webstats-tb is willing to graph data before it has the full set of data points for the most recent day. Is that a plausible bug here?

In particular, weasel seemed to think that it was graphing today's data using input from only one of the four webservers.