Here are instructions for using Snapshots to revert macOS to a prior version.
Note: this will not affect data stored on external disks. Reverting to a prior snapshot only affects information stored on your System volume.
1) Shutdown your M1 Mac
2) Restart and hold the power key, until you see “Loading startup options”
3) Click on “options” and continue
4) Click on your startup volume
5) Select your admin account and enter password
6) Click “Restore from Time Machine”
7) In the info window, click “continue”
8) In the “Select a Restore Source” window, Select your startup volume and click “Continue”
This brings you to the Select a Local Snapshot” window.
9) Select the desired Snapshot. (generally, this is the last Snapshot on the list, i.e. you need to select the last Snapshot with 11.1, which will revert the system to this point in time.)
10) Click Continue, affirm again by clicking “Continue”
The system will automatically restart and startup from the restored Snapshot.
If you don’t have a Time Machine backup or Intel Mac
If you don’t have access to a Time Machine backup or an Intel Mac you can temporarily use, we have listed instructions to perform a factory reset of your M1 Mac to regain access to your SoftRAID volumes.