Just as an update if anyone else reads this post – the WP INBOX plugin https://wordpress.org/plugins/wp-inbox does not allow you to send mass emails to different User Roles. So back to the drawing board.
If anyone else knows how to do this please let me know.
Thank you for your reply! I’m apprehensive to use plugins that have been abandoned by their developers (Sitewide Newsletters). I’m going to try out this plugin WP INBOX plugin https://wordpress.org/plugins/wp-inbox & if it works for us then upgrade to the paid version.
It doesn’t allow us to email our BuddyPress groups, but it will allow us to contact our members & various User Roles which will be helpful.