Issue with remotely triggered Jenkins (REST API) jobs not sending emails;

job log:
Email was triggered for: Always
Sending email for trigger: Always
An attempt to send an e-mail to empty list of recipients, ignored.

1. Same job ran via build now in gui is able to expand the $DEFAULT_RECIPIENTS and send emails.
2. Harding code an email address in the field "Project Recipient List" works with REST API jobs.
3. $DEFAULT_RECIPIENTS or any variables is not expanded with REST API jobs.