Build 26300.7965 is a new Windows 11 Insider Preview build for devices enrolled in the Dev Channel and is being delivered through Windows Update. To get it, the device must be configured for the Dev Channel in Windows Insider settings and then check for updates under Settings > Windows Update.
If Release Preview or Beta content is appearing unexpectedly on a device, this can be related to temporary channel configuration issues on the service side. In recent similar cases, Release Preview visibility was briefly affected and then restored after Microsoft resolved the issue on the backend.
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