Time Machine doesn't back up the OS, but you can reinstall the OS yourself on to a blank drive using Internet Recovery, if they're going to charge you to do it.
Okay, just googled that and I think I’ve actually done it in the past... Thanks.
@withered_preacher started
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Time Machine doesn't back up the OS, but you can reinstall the OS yourself on to a blank drive using Internet Recovery, if they're going to charge you to do it.