Usually the Competitions lock 5 minutes before the first match of the Matchday currently running in a Competition after which you are not allowed to enter prediction until the next matchday will open.
The Predictions By Computer are automatically posted daily for the matches that are shceduled to play in that specific day. You can go up to 6 days back to see the previous predictions. With green color are the correctly predicted results on the 1X2 column whereas with red color are the wrongly predicted by computer results on the 1X2 column.