Time machine transfer: Case Sensitive File systems

The goal is to migrate a user account from a BigSur MacBook to a Sonoma MacBook. A SSD time machine backup was created last night. Migration assistant was invoked and the SSD was selected: The source is not using a Case Sensitive filesystem, while your Mac is. The BigSur backup is greyed out,so I have "hit a wall". I can select the backup however, the continue button remains grey / inoperable What can be done to overcome this problem? Do I have to reformat the new MacBook with a Case Insensitive version of APFS and then reinstall Sonoma? Or is there a work around?