Recurring Invoice Question (Self-Hosted)

I have my fixed price recurring invoices setup with no issues.

However, I offer my clients managed off-site back, and bill based on GB used/month.

Is there any way I can have these set of invoices generated and sent automatically monthly?

I do get a report (excel file) e-mailed to me from said service containing client names and usage.


It may be possible to set it up with Zapier.