Restore from a Time Machine Backup for Specific Date
I'm trying to fix my mom's MacBook Air from 2014 running Big Sur. After a recent app update, she found many files and all of her music were missing. She spent time on the phone with Apple Support and they had her reinstall her OS...but didn't tell her she'd lose all her files, settings, etc. Ugh. Luckily, everything is backed up to a Time Capsule through Time Machine. I want to do a full restore that takes her back to a specific date prior to when things went bad. I want the entire computer to be exactly as it was on that date. Browsing through Time Machine, I've confirmed Time Machine has a backup for that date and several others around it. Since I don't just want to recover specific files, I'm using Migration Assistant. But when I use Migration Assistant, I don't have the option to choose a date. It shows me the date of the last backup. I absolutely do NOT want the last backup--because that was after the new OS was installed and the computer wiped clean. Can someone please walk me through how to do this?
[Re-Titled by Moderator]