(7). Extent relative time (BeginTimeE, EndTimeE)
Specifies the location of ISO files that are file interleaved. Used to indicate the positional relationship between interleaved files. An error occurs if it is specified outside the defined in the Extent line.
The specified time is expressed as (minute: second: frame) time with 00:00:00 as the start of the extent.
If you want to specify the location within the session, specify the location of the interleaved files together with the argument on the Extent line.

(8) .File relative time (BeginTimeF, EndTimeF)
Specify the location of the file source in the ISO file. An error occurs if it is specified outside the file source definition. The specified time is expressed in (minute: second: frame) time with 00:00:00 as the start of the file.

When defining an ISO file that is channel-interleaved, you can specify the position of the channel in the ISO file by specifying BeginTimeF or EndTimeF in the file source definition that makes up the channel, and you can define the positional relationship between the channels.
The start of the file source that makes up the channel is the start position of the channel, and the end of the file source is the end position of the channel.