There are so many questions this leaves unanswered:
- Was this a one-off error in Cloudflare's processes? (These things happen on a big enough scale.)
- Were you violating a specific clause of Cloudflare's T&C? How clear was the clause? What did you do to fix this?
- Was the issue that Cloudflare estimated that you're not paying enough given the bandwidth you're consuming? Did you end up signing up for the Enterprise plan?
Transparency would benefit both Cloudflare (in not making people unnecessarily apprehensive about becoming/remaining a customer) and you (in demonstrating that you're handling this issue in a professional and responsible manner).
That is rather aggressive?? Maybe thry live in another time zone and are asleep, or have other obligations like school pickup. Given them at least 24 hours to respond. sheesh...
And to requote the OP back to you like I did above, given that customer support told them there's a 24hr limit to that ban becoming permanent and tried to help them get it resolved before then, in this case it was in fact entirely reasonable to expect at least a one-line update within (in this specific case) a day, since either way the outcome would be known.
And in fact here's the OP's followup post: https://news.ycombinator.com/item?id=34721870