I use the baseball/lead-off analogy quite a bit to refer to a range breakout that occurs before the important event that is most likely to cause a breakout. In the current case, that event is actually a series of events culminating in next week's Jobs Report.
Next week is important in a general sense because it's the first week of December, and it marks the start of the final approach to the end of the 2018 trading year. The first 3 weeks of December frequently see an uptick in bond market momentum. Individual focal points frequently include the jobs report and the Fed announcement that follows roughly 2 weeks later.
With the sideways momentum strongly intact on the first 3 days of this week, we were getting closer and closer to that first week of December. But as of this morning, bonds may be interested in taking a lead-off.
As the chart suggests, such a lead-off morphs the previous sideways trend into a rally trend. It also keeps the shift in short-term momentum at bay (blue/red lines, with the last notable spike from flat levels highlighted in late August).
Keep in mind though: it's a rally trend as of today! Tomorrow could change that. As soon as we see a momentum shift like the one in August, it will be time to get more defensive. If that spike arrives before next week's jobs report, I would only get as defensive as I needed to get, on the chance that the jobs data reinvigorates the rally.