If you have set Blackouts using the Program Blackout Calendar they will appear on the Cycle Grid, alerting you that a Program Location is unavailable during the selected time frame.
A Blackout will appear on the Cycle Grid as dark grey boxes to indicate that you have assigned a Blackout to this Program Location during this time frame. If you would like to make this Program Location available for the given time frame, you must go back to the Program Blackout Calendar and delete the Blackout.
Blackouts when adding Available Activities to the Cycle Grid
When adding a new Available Activity to a day within a Cycle, if you have a Blackout during any of the given Periods, the Period will appear italicized and crossed out.