Can I load speakers in and then add headshots and speaking times at a later date?

Yes. You can upload the speakers individually or in one batch, go to Data and then  Speakers  and see the instructions there to upload them. Just leave the column for speaker headshot urls blank if you're doing a bulk upload without headshots.

 

Once you've uploaded them you can go back to the  Speakers section and click on the circle in the  Headshot column to upload a headshot.

 

You can then go to  Data and  Sessions at a later date - again loading them individually or in bulk.

 

Once you've uploaded them you'll need to connect speakers or sessions, or vice versa. You can do that in either the speakers or the sessions section.