Speakers not receiving email for published, free, recurring event.

Hi - I’ve just published a recurring weekly event. We will have different team members covering sessions, so I didn’t have any speakers added when I published. 

I’m adding speakers now and they are not receiving the email invite with calendar link.

The sessions are published. 

Registration is required.

They all have special role of speaker. They’ve all been added as “speaker.”

I’m adding them per session here:
 

The speaker session join details email is scheduled for 4 weeks out - but sessions start next week. 

Am I missing something? Is there a way to set these to send as soon as I add someone as a speaker? Or is there even a way for me to manually send them?