To only view the last x amount of time, select the desired time range from the start time until the most recent time using the timeline. When the selected time range includes the most recent time (the selection is all the way to the right of the timeline), the amount of time selected will stay constant but always be updated to include the most recent time. This is equivalent to a "tail" of data for a selected window of time.
The tailing feature can be seen above as a period of time, including the most recent time, is selected. As new data streams in, the amount of time selected remains constant but the window of time shown in Tiles is updated to include the most recent data. Older data slides out of view while newer data slides into view.
This feature can be used to show and update the last 24 hours, 1 day, 1 week, etc. amount of data.