Can I change the report after creating it?

Yes, by talking to it: "drop the returns column" or "send it on Thursdays too". No need to rebuild from scratch.

What if a platform is down that day?

The report still arrives with whatever could be read, and says explicitly which source was missing. That beats an incomplete number presented as a complete one.

Can someone without an account receive it?

Yes. Email delivery goes to the list you define, account or not. WhatsApp delivery does require the person to be enabled.

Automated sales reports, without building the spreadsheet

Set the report up once and receive it on its own, as Excel or PDF, over WhatsApp or email. From your store, CRM or ERP data. 7 days free.