My MacBook Pro is stuck in 'Installer Progress' mode!

An hour on the installer progress screen does sound like it might be stuck. Here are a few steps you can try to get your MacBook Pro moving again:

• Force Restart: This might seem simple, but it's often the answer. Hold down the power button for about 10 seconds until your MacBook Pro completely shuts down. Then, wait a few seconds before powering it back on.
• Boot into Safe Mode: Booting into Safe Mode performs a basic startup and can sometimes resolve installation issues. Restart your Mac while holding down the Shift key. This will take longer than a normal startup. Once booted, try running the update again.
• Reset SMC and NVRAM: SMC (System Management Controller) and NVRAM (Non-Volatile RAM) manage low-level functions on your Mac. Resetting them can sometimes clear up glitches. You can find instructions on how to do this on Apple's Support website [Apple Support Reset SMC NVRAM].
• Reinstall macOS in Recovery Mode: If none of the above work, you can try reinstalling macOS. This will not erase your data, but it's always a good idea to have a backup just in case. Restart your Mac while holding down Command + R. This will boot your Mac into Recovery Mode. Here, you can choose the option to "Reinstall macOS."

If you're still having trouble after trying these steps, you can check the Apple Support website for more troubleshooting tips, or contact Apple Support directly. There might be an underlying issue that needs further attention.