revert to 12.3.1

Of course- I was putting it there for the benefit of the original poster :)

As for data migration, I don't think so. As far as I know, you can restore backups from older to newer versions of macOS, but not the other way around. It could certainly be tested with Migration Assistant, though.

Data migration would likely have to be done manually, however. While not the most elegant solution, if RingGuy12 needs the monitors working again, there isn't much of a choice.

You can-

Making The Installer

1. Make a backup of your data.

2. Open the Terminal app and enter this command EXACTLY as shown, then press Return-

softwareupdate --fetch-full-installer --full-installer-version 12.3.1

3. Move the installer it generates into your Applications folder.

4. Connect the USB flash drive or other volume that you're using for the bootable installer. 

5. Going back into Terminal, enter this command EXACTLY as shown, then press Return (IMPORTANT: You need to either change the name "MyVolume" in the command to the name of your drive, or change your drive name to "MyVolume" [no quotation marks] to install it correctly-

sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

6. When prompted, type your administrator password and press Return again. Terminal doesn't show any characters as you type your password.

7. When prompted, type Y to confirm that you want to erase the volume, then press Return. Terminal shows the progress as the volume is erased.

8. After the volume is erased, you may see an alert that Terminal would like to access files on a removable volume. Click OK to allow the copy to proceed. 

9. When Terminal says that it's done, the volume will have the same name as the installer you downloaded, which should be "Install macOS Monterey". You can now quit Terminal and eject the volume.

Booting From The Installer

Apple Silicon

1. Plug the bootable installer into your Mac (must be connected to the internet). A bootable installer doesn't download macOS from the internet, but it does require an internet connection to get firmware and other information specific to the Mac model.

2. Turn on the Mac and continue to hold the power button until you see the startup options window, which shows your bootable volumes.

3. Select the volume containing the bootable installer, then click Continue.

4. When the macOS installer opens, follow the onscreen instructions.

Intel Processor

1. Plug the bootable installer into your Mac (must be connected to the internet). A bootable installer doesn't download macOS from the internet, but it does require an internet connection to get firmware and other information specific to the Mac model.

2. Press and hold the Option (Alt) ⌥ key immediately after turning on or restarting the Mac.

3. Release the Option key when you see a dark screen showing your bootable volumes.

4. Select the volume containing the bootable installer. Then click the up arrow or press Return. 

5. If you can't start up from the bootable installer, make sure that Startup Security Utility is set to allow booting from external or removable media.

6. Choose your language, if prompted.

7. Select Install macOS (or Install OS X) from the Utilities window, then click Continue and follow the onscreen instructions.

Hope that helped!

Is the computer an Intel or Apple Silicon M1 / M2 computer?

Using certain Terminal Command it is possible to download a version 12.3.1 and as others have mentioned, create a Bootable Installer.

 softwareupdate --fetch-full-installer --full-installer-version 12.3.1

But depending which type of computer and Scorched Earth Approach could be used to Wipe the Entire Drive from the Bootable Installer and lay down a Clean Version

Understand the Below will ONLY Work on Intel Computer

Scorched Earth Method 

This method will WIPE ALL Data and there is No Recovery - Period.

To perform this action will require booting from a Bootable Installer. 

The Bootable Installer can Only be performed on an Apple Computer 

This will have to be performed from a Qualifying Computer to run the version of macOS to be made on the Bootable Installer.

Example Only : Bootable Installer of Big Sur would have to be done on a computer that Qualifies to run Big Sur.

Notation: If the computer being used to perform this action is Too New or Too Old to qualify to run the version of macOS - this computer can not be used.

Alternative is, to gain access to a Qualifying Apple Computer from a family member, friend or associate.

Extra Special Notation regarding the Touch ID equipped Apple Computer.

About Startup Security Utility and Must Enable from Recovery Mode the ability to boot from External Drive Before Attempting 

1 - Shutdown computer and disconnect all external drive Except the newly created Bootable Installer.

2- Restart and immediately hold the OPTION key until the Startup Manager appears and choose the USB Drive. 

3 - It will present options >> Disk Utilities >> View >> View ALL attached Drives. 

4 - Choose the Upper Most Drive ( not the volumes indented and list below ).

5 - The drive normally is called Apple Media or Apple SSD - that is the drive to Erase and format as APFS with the GUID Partition Map. This applies to macOS 10.14 Mojave and above. 

6 - Once that is done >> backup out of Disk Utilities and choose install macOS. 

7 - Follow the prompts and it may automatically reboot several time. 

8 - Upon a final reboot - Setup Assist will present with the newer version of macOS.

I have a question about this. If you download 12.3.1 from the Terminal, then create a bootable installer, are you saying you can't erase the drive, install 12.3.1, then migrate the data from a 12.4 Time Machine backup?

VikingOSX wrote:

You have the spare Macs, test away… 🧐 Sounds feasible, yet I have no idea if what you suggest will work without Apple throwing a wrench in there somewhere.

Okay. I just wanted to check. Thanks.

Unless you have a Time Machine backup that ended with macOS 12.3.1, and then not used again for Time Machine for 12.4, there is no reverting to macOS 12.3.1.

You have the spare Macs, test away… 🧐 Sounds feasible, yet I have no idea if what you suggest will work without Apple throwing a wrench in there somewhere.

___Bubba___ wrote:

Hope that helped!

Thanks. I knew that. I was asking if once that was done if it was possible to migrate the old data over. Not how to do it. :)

___Bubba___ wrote:

Of course- I was putting it there for the benefit of the original poster :)

I see. Since you replied to me I jumped to the conclusion you were addressing me. 😎

Sorry, wrong button! ;)