Sequential Autoresponder

Hello,

I have done some basic , filters, and regex in bat, and now I would
like to implement this.

The basic idea is I have a free learn to play guitar email course, that I
want to send out to subscribers over a period of days.  There are 7
lessons and ideally each lesson would get sent one per day.  As new
students come on aboard they start with lesson one and progress up to
seven.

This is the hard part, a broadcast newsletter is easy, simply email
the same thing to many people, but how to email a sequence of emails
automatically and individually.

Thanks for the suggestions,

Tom