When creating new CRM constituents with an email address, or adding new email addresses to existing constituents, sometimes the records aren't being updated in LO.
If a new constituent record is created with an email address supplied during creation, please check the Sync history detail if the email address is not showing up in Luminate Online after the sync process is run as there is likely an error for that record.
If a new email address is added to an existing constituent record and the LO Sync isn't updating the Luminate record with that email address, check the LO Constituent Sync options and make sure the Sync email from BBCRM to LO checkbox is marked. To explain further, email is required for creating LO constituents for the sync, since so much relies on it. Therefore if the sync is creating an LO constituent based on the CRM constituent, then it will add the email no matter what. However after that, without the "Sync email from BBCRM to LO" box checked, further updates to the record's email addresses in CRM will not sync to LO.