qTest ↔ Jira: Zero‑Downtime Incremental Sync of Test Data During Live Migration

We need to migrate a small application’s test artifacts from an existing qTest instance to a new deployment while keeping the system online. The goal is to preserve continuity for both test execution and defect tracking in Jira.

The primary constraint is the lack of a single‑transaction migration path. qTest’s REST API supports incremental pulls via the modifiedSince filter, but a final catch‑up sync is required afterwards. A full export/import wizard locks the source database, causing a brief outage that we want to avoid.

Uncertainties revolve around the trade‑off between an incremental, continuous sync that might miss late changes, and a full dump that forces a short downtime. Clock drift between the source, target, and migration tool could also lead to duplicate or missing records.

What is the most reliable strategy to guarantee zero data loss when using the modifiedSince incremental API during a live migration?

Should a final catch‑up sync be scheduled after the migration window, and how can we verify that no records were missed?

What best practices exist for synchronizing custom field mappings and ID translation between the two qTest instances during incremental transfer?