How to exit Win11 Insider Preview Build 26220?

Build 26220.8764 is an Insider Preview, so opting out changes enrollment; it does not become retail, and expiration will not do so. Open Settings > Windows Update > Windows Insider Program > Stop getting preview builds and confirm “Unenroll this device when the next version of Windows releases” is enabled. If Microsoft designates a matching production build, Windows Update can move the PC onto production servicing without removing personal files. Until then, install Insider updates so the build does not expire. Do not assume 26H1 retail cumulative updates will apply while this preview branch remains installed. If stable Windows is needed immediately, back up files, the BitLocker recovery key, and app settings, then use Microsoft’s Windows 11 recovery or installation media. Moving to a lower stable build can require a clean installation, which removes apps and may erase data. Check winver and the Insider page after restarting to confirm status.