The table planner is a tool to help organizers always be on top of what is going on.
All matches will pop up as you plan them in the tournament, as soon as you set a date/time and a table for a match.
As seen in the header picture, the tables will be marked Green in the left column as soon as a match is finished and the next one can be started.
Most managers can easily be on top table status, but when there are multiple tournaments (like qualifiers) going on at the same time, it might be a different story. For these cases, the table planner is very helpful, as it shows what tables are in use and for what tournaments, indicated by color.
The matches that are in play are shown with a small blue pulsating circle, so you can easily spot which matches are in play.
If a match has been going on for a long time, and perhaps you considering setting in on a shotclock, you can click the match and see the score. Example below.