From PTT pane of Command Center it's possible, for recorded channels, to consult the current channel history of last 10 speakers during the last 24 hours.
1. Go to Command Center page under Logbook menu.
2. In left pane click on the microphone icon (Push-To-Talk text appears) to show it.
3. Select desired channel. It must be a recorded channel to generate an history. This will be indicated by a message in the orange ribbon right above the speak button.
Click then on the blue icon on the right.
4. This will open a new tile presenting last 10 speakers for the previous 24 hours (otherwise empty). You can click on Go to PTT history button in bottom right corner to directly reach PTT Recordings page.