You should receive an email notification once all participants have completed the assessment.
You can also check the status of your dispatch in CompetencyCore. Go to Assessments > Dispatches. Deselect the My dispatches checkbox on the top left of the table if you have the Assessment Administrator permission and want to see dispatches created by another user. Check the overall completion status in the Status column. To check the status of individual participants, click the external link icon in the Participants column.