I don't think it will be in the upgrade centre Dave as none of the other pre-built solutions have appeared in the upgrade centre (least not for me).
I'm very wary of this solution anyway - I know it includes settings for obeying the email limits of your ISP, but realistically if you're regularly sending hundreds of emails to the same addresses each month your ISP is going to notice sooner or later.
I suppose it will depend on how often you email your customers and how many customers you have really.