To start punch and roll recording, you must select a region in the audio file, otherwise, the button will be grayed out, and click "Punch" from the Recording Tab. The audio will start playing 3 seconds before the selected region and start recording. After the duration of the selected region, it will also play 3 seconds after the recording. The playback time can be configured in "Record Options" -> "Punch and Roll Settings".
There are different record modes in Punch and Roll Recording. The "Auto" mode chooses between "Fixed" and "Flexible" smartly based on the type of audio we are recording over. The "Fixed" mode automatically stops based on the duration of the selected region. "Fixed" mode is recommended for music audio types. The "Flexible" mode continues recording from the selected region and stops until user decides to. "Flexible" mode is recommended for voice audio types like podcasts, etc.