The recording creates a new file approximately every 2 hours (or approx. every 2GB).
For example, if you have a recording running for 4 hours and 25 minutes, you would then have 3 files. The first recording would be the first 2 hours, the second recording would be the subsequent 2 hours, and the third recording would be the final 25 minutes.
A new recording is made every time they stop a stream and start another. For example, if all presenters/hosts stop streaming and leave for a break, the recording will stop. A new recording would start once a host rejoins the stream.