There isn’t a specific template that you can store other than the single default template that is stored with the plugin settings. WHat you can do though is use draft posts to store your templates and then use the draft post content to seed the email send later.
mmm i don’t understand how to seed a mail with a draft post ?? How to do this?
I think you misunderstood what I meant. You can use a draft post to save your templates. When you want to use one, you copy the content from it paste it into the body of the email you want to send. Not super elegant but it does work.