Checking Cloudflare's plans and based on the above, they are using the second most basic plan available.
Yes you are correct. I got my notes mixed up. It is the Enterprise that is invoice only:
https://www.cloudflare.com/enterprise/
Pro and Business plans are billed using credit cards. Enterprise customers will receive a monthly invoice
I originally looked into this when the credit card wasn't paid. I think the point though remains the same; for a 'bank' why are they not using the very best service, protection and up time guarantee. It is not like this is the first time this has happened. Off-hand I can think of 3 critical periods when the markets have been most active. This might be the 4th time now?
In particular Enterprises' '2500% uptime guarantee' whatever that means. Maybe Cloudflare will reimburse Kraken customer's who lose profits on trading owing to the site being down?