So updating the rules is not the same as updating the software? Who says this is different here? How do you define the difference between a "tax rule" and business logic?
The changes go beyond tax band thresholds and percentages across NIC & IT. Eg the (now-scrapped) Health & Social Care Levy would've been a completely new tax - you need a complex schema to encode that and even then the Treasury will come up with something you haven't thought of next.
The changes go beyond tax band thresholds and percentages across NIC & IT. Eg the (now-scrapped) Health & Social Care Levy would've been a completely new tax - you need a complex schema to encode that and even then the Treasury will come up with something you haven't thought of next.