To allow for an early payment registration discount, create a Group Registration Attribute for payment options (Groups & Events > Settings > Registration Fields, with the one of those drop down choices being "Early Bird Price" or something similar.
As you create the values in your drop down list, put a Registration Limit (see image below) for the Early Bird price if this is limited to a certain number of first registrants. If the Early Bird discount is available through a certain date range, on that particular date go back into the Registration Attribute and edit this limit to the the number of Registrants in the group on that date to close the Early Bird option out.
- To associate your newly created Registration Attribute to your Group/Event, go to the Group's page, click the blue Registration > Settings. Add the Registration Attributes from the drop-down menu found toward the bottom of that page under "Registration Fields." You can also add new or edit existing Registration Attributes by clicking the "Customize Registration Attributes" on this page.
To use a "Late Registration" payment option, you will take similar steps as above, only create a drop-down value in your Payment attribute called "Late Registration" or the like. Once the date arrives for the late payment fee to be charged, go to the payment Registration Attribute for your Event and edit the Registration Limit for the regular payment option to be the number currently in the group (minus your early birds if you used that option), closing that option out.