Unserialize error: Error at offset X of Y bytes when updating URLs with wp search-replace

The goal is to move a small WordPress site to a new domain or server without any noticeable downtime, using WP‑CLI to export the database while the web server continues to serve cached pages and then import it onto the target environment.

After the import, the site URLs must be updated, but the built‑in wp search‑replace command is known to break serialized PHP strings when the replacement length differs from the original, which can manifest as 'Unserialize error: Error at offset X of Y bytes' when loading options, post meta or widget settings. An unresolved decision is whether to rely on wp search‑replace with the --skip‑columns=guid flag or to adopt a third‑party serialized‑safe replacement tool that preserves the integrity of serialized data during the zero‑downtime window.

Is it safe to use wp search‑replace with --skip‑columns=guid for all tables when the replacement string length changes? Does employing a serialized‑safe replacement tool introduce measurable overhead or risk during the brief migration window? What verification approach can confirm that serialized data remains intact after the replace operation without taking the site offline?