#10448 docs: explain why incremental runs resend rows Pull request opened by lavkushry Summary • Explain that incremental replication is at-least-once and often re-emits the bookmark watermark; destinations should upsert/dedupe. Fixes #3426 Test plan • Preview the new subsection under Incremental replication state Summary by Sourcery Explain the expected at-least-once behavior of incremental replication and how to reload historical data when needed. Documentation: • Document why incremental replication may resend rows at the bookmark watermark and advise destinations to upsert or deduplicate them. • Clarify how to perform full historical reloads, including the interaction between --full-refresh, start_date, and custom extractor state files. meltano/meltano