How does my Roamio record the whole live hour?

I've noticed that my Roamio can start a recording of a live show already past the 30-minutes buffer, yet it still starts at the beginning, say, 40 minutes ago. How does it do that? My previous Series2 could only pick-up at the beginning of the buffer

How does my Roamio record the whole live hour?

How does my Roamio record the whole live hour?

I've noticed that my Roamio can start a recording of a live show already past the 30-minutes buffer, yet it still starts at the beginning, say, 40 minutes ago. How does it do that? My previous Series2 could only pick-up at the beginning of the buffer

How does my Roamio record the whole live hour?