It's timecode. I use Ardour and the default clock is timecode. Reaper defaults to bars and beats, but also has minutes and seconds. What is exported will also depend on what the snap is set to, which could be different from the primary clock. The format usually tells us what the clock is.
timecode : hh:mm:ss:ff
minutes and seconds : hh:mm:ss.sss
So I don't know where 09:0633 came from or what it means exactly.