This help doc will demo how to override the delivery method on the event level. This would be used if an event has a different delivery method than the global settings.  

Head over to the event you would like to edit. Select EDIT EVENT INFO from the "select action" drop-down menu. On the left side navigation select FEES + ACCOUNTING.

From this screen, you can edit the delivery options for the event. Changing this setting will override the global settings.

NOTE: An order can only have ONE delivery method.