Appointments+ email confirmation to multiple email addresses, with different contents?

Is it possible to send client confirmation emails to more than one email address, ideally containing different content?

I have an email->SMS gateway which will accept emails to phonenumber@mysmsgateway.com and convert them to SMS. I would like Appointments+ to send 2 confirmation emails to clients, one to their email address and one to client-phone-number@mysmsgateway.com (with client-phone-number being a variable populated from the PHONE field)

If possible I would like to be able to send a different email to both addresses so as to keep the SMS confirmation short.

I have seen there is a plugin which supports a couple of SMS gateways but sadly not mine, however if I can set up an additional confirmation email as outlined then this would solve my problem.