January 2026 delivered foundational billing and security enhancements across Azure/ARO-RP and Azure/ARO-HCP, focusing on reliable billing document workflows, lifecycle correctness, and platform security. Key work included launching the Billing Documents API with admin endpoints and route simplification to enable easier integration and reliable billing operations, backed by structured data models and tests. CosmosDB trigger improvements fixed deletionTime handling for billing documents and refactored triggers for readability to reduce regression risk. In ARO-HCP, updated security posture with AMEV2 root certificate deployment, updating PEM and Bicep references. These efforts improve operational reliability, accelerate billing-related integrations, and reinforce platform security and maintainability.