Blogger Support, in observing the confusion caused by the recent email about unmigrated legacy Blogger accounts, has taken action to reduce the confusion.
For the people unsure or unaware of what un migrated legacy accounts they may have, they now have a "Blogger legacy account data request" form. It's a very simple form - but you will be expected to exercise patience, before you receive actual detail.
Retrieving details about un migrated legacy accounts is very simple, for any account owner, having received email about an "unmigrated legacy Blogger account".
Provide the email address, where you received the "unmigrated accounts notice".
You immediately get a simple acknowledgement.
The process of retrieving the legacy account details is not automated. Once you submit your email address, and get the simple acknowledgement, you may have to wait 2 or 3 days, before you get email with the anxiously awaited details. But you have a month to get the migration completed.
So get started, this week - and get this portion of your life out of the way.