The challenge
Billing had been built incrementally and handled the simple case only. Mid-cycle plan changes were adjusted manually, failed payments were chased by hand, and domestic and export invoicing required separate manual treatment. Finance spent several days each month reconciling.
What we did
We rebuilt billing around an append-only subscription event model so every state change is recorded and any past position is reconstructable. Proration, upgrades, downgrades at period end and trial conversion were implemented and tested against a comprehensive case matrix. Dunning sequences were automated for failed collections, and invoicing was built to handle GST on domestic sales and zero-rated export treatment separately.
The outcome
The monthly manual reconciliation was eliminated. Involuntary churn from failed payments reduced once automated dunning was in place, and finance gained invoicing that reconciles without adjustment.