Fix BitTitan Migration Dates in Google Workspace

BitTitan MigrationWiz uploads emails to Google Workspace through the Gmail API or IMAP. During the upload, Google's mail infrastructure records the insertion timestamp as the message's INTERNALDATE. BitTitan also introduces a Received header dated to the migration. The original Date header inside the email body stays intact - but the INTERNALDATE is gone, overwritten with the migration timestamp.

The thing is, Google Workspace handles this differently from other platforms. Gmail's web interface reads the Date header for display, so emails actually look correct when viewed in the browser. But the IMAP INTERNALDATE is permanently set to the migration date. Any IMAP client connecting to that Google Workspace account - Outlook, Thunderbird, Apple Mail - reads the INTERNALDATE and shows the migration date instead.

This creates a maddening split. The same email shows the correct date in Gmail on the web but the wrong date in Outlook connected to the same account. IT administrators get conflicting reports. "My emails are fine." "My emails are all wrong." Both users are right - they are just using different clients.

You just migrated 85 mailboxes from on-premises Exchange to Google Workspace using MigrationWiz. Half your team uses the Gmail web interface and sees nothing wrong. The other half uses Outlook via IMAP and opens 85 support tickets in one morning. Diagnosing it takes hours because the problem is invisible in the MigrationWiz console and in the Gmail admin panel.

The dual-date problem hits hardest in organizations where users access mail through multiple clients. Gmail web looks fine. Outlook looks broken. Apple Mail looks broken. Mobile IMAP clients look broken. Only the web interface masks the problem.

But it goes deeper than display. Google Vault (the compliance and archiving solution used for legal hold and eDiscovery) references the INTERNALDATE for certain operations. Date-based legal discovery searches can return inaccurate results. Third-party backup tools connecting via IMAP archive the migration date as the message date, creating permanent inaccuracies in backup records. Even Gmail's own IMAP SEARCH DATE command uses INTERNALDATE rather than the Date header.

Redate.io resolves this through a multi-stage header analysis pipeline that corrects the INTERNALDATE and migration headers without touching the email content or attachments. The Gmail web experience (which already looked correct) stays unchanged, while IMAP clients, Vault, and backup tools all start reading the right date. Pattern matching across migration tool signatures ensures only BitTitan-injected headers are targeted.