Within VolunteerMatters, an administrator with the proper privileges can select a shift, or multiple shifts, from a volunteer calendar and then assign multiple contacts to muliple volunteer shifts simultaneously.
This functionality is available for all Pro and Enterprise subscribers.
To do so you will log into VolunteerMatters and click on Admin > Volunteer Calendars and then click on Shifts for the Calendar you wish to assign contacts for. You can also click on Admin and then click on the Volunteer Calendar icon directly. Then you can follow these instructions:
1 - Select the volunteer opportunities where you wish to assign contacts to shifts via the checkbox on the far left and then click "assign" icon ()
2 - This will open the "Assign Users to Shift(s)" page. Then click on "Choose" and use the chooser to select any number of volunteers. When you click "OK" It will add all selected contacts to the contacts area of the page. You can then add optional "Admin Notes" and then click the "Assign" button to add all selected contacts as assignees to all of the selected volunteer opportunities.