Settings and limits are automatically handled by AB Bulk Mailer software to ensure maximum delivery in minimum time. It sends emails based on per day and per hour limit of an SMTP. You can keep a regular check on the emails to prevent your accounts from getting blocked.
You can add the SMTP servers from free senders like Gmail, Yahoo, outlook etc. Your own website emails and dedicated SMTP servers can be added where the limits can be checked with the hosting company.
You can add unlimited SMTP servers in the software. You can keep a check on the limits of all your SMTP servers and save them from blocking. The software does not have any inbuilt smtp server.