"blog level" or "user level" for BuddyPress "Automessage" plugin ?

Which option is used to send auto messages specifically for BuddyPress ?

I am assuming "blog level" refers to creation of a new site under WP multisite.
Currently I have "user accounts can be created" under "Network Settings" >> "Registration Settings",

therefore leaving site creation out for now.
The main site is however set up as a WP multisite.

"user level" is the appropriate choice for sending automated emails to new BP members ?

this is no specific mention for BP on the description page ;

any kind assistance in this would be greatly appreciated,

kind regards,