How do you handle timezone-related test failures in a distributed team?

We have engineers in India, UK, and US. Our tests occasionally fail due to timezone-dependent logic: - Date range filters that work in one timezone but not another - "Created today" queries that break at midnight UTC in one timezone - Scheduled job tests that assume server timezone Current workaround: all CI runs in UTC, local development also forced to UTC via `TZ=UTC` env var. But we still get failures when: the test uses `datetime.now()` without timezone awareness, or when the application has hardcoded timezone assumptions we haven't found yet. Any systematic approach to finding and fixing timezone-naive code in tests and application code?