One Step Update Trashed My Accounts This Morning

This morning, February 3, during "One Step Update" there was a message that said something like "Updating Cloud Data for New Format (one-time process) This may take a while". Then the system proceeded to trash my accounts adding in bogus transactions and deleting valid entries. Luckily I have a backup from a week ago and can reconstruct the past week's entries, but this is horrible that I have to spend time reversing the damage.