Run, monitor, and resume a migration

Read the progress screen

The progress screen names the current phase and reports saved snapshots, copied values, verified values, and conflicts. Field Renamer adjusts the next batch size from the work the server completed within its limits.

Use the estimate as a planning range

The impact review estimates duration from the preflight count and the observed per-record rate. Database speed, object-cache behavior, and server load can change the result. A large migration may take several minutes while each request remains short and recoverable.

Keep the maintenance window open until the operation reaches Completed or you safely abandon it before cutover.

The selected field is write-protected

ACF displays the affected field as read-only while an operation can still resume or recover. WordPress and ACF metadata hooks also block writes to the protected field and objects. Other fields stay editable.

Closing the tab does not discard completed batches

Each completed batch updates Migration History. Reopen ACF → Field Renamer if the browser closes or the network disconnects. An active operation resumes from its stored phase and cursor; it does not restart the completed work.

Server backoff

The browser starts the next batch after a short delay. If WordPress reports a busy or transient server condition, Field Renamer increases the delay before trying again. The five-second and 5 MB request limits still apply, and the saved cursor prevents repeated completed work.