Does Aegir 3 allow multiple SSL sites on the same IP Address? On our server some sites use SSL, some don't, some are Drupal sites, some are not.
All the sites are served at the same IP address and the non-Drupal sites each use their own certificates (or none) per their Apache configuration. 

With Aegir 2 it was only possible to have: one IP Address for non-SSL sites and one IP address per each SSL Drupal site which would exhaust our purchased IP addresses.  

Does Aegir 3 allow multiple SSL sites / certificates on the same IP address?
Indeed it does. From the release notes:


  Aegir 3 now supports SNI for SSL.