This document discusses pre-day 1 onboarding data flow. It explains that recruiting sends candidate and applicant IDs to onboarding. Onboarding then sends these IDs plus a unique HRDataID to its management data file table after post-hire verification. This allows managers to provide pre-day 1 access to new hire onboarding content. When new hires complete onboarding paperwork, employee central pulls over the data including HRDataID. After hiring, employee central matches new employees to their pre-day 1 records using HRDataID to merge the temporary and permanent records. The data flow ensures a smooth pre-day 1 onboarding experience.