I can see the value in a product like this. There's a lot of complexity in billing based on premium rating, fx rates, taxes in different states/countries, etc. that are constantly changing. Maintenance teams struggle to keep up with the requirement changes and there are a lot of weird defects and missed requirements that make their way into billing. It's taken as a given that our financial system will include mistakes that need occasional manual correction. So if the blockchain is going to emerge as the new industry standard ledger system, there needs to be a way to correct mistakes.