Answer: The same thing just happened to me recently (after all these years of tomato growing!). From what I have uncovered, the brown spots are evidence of trauma. The tomatoes were stressed by too much light and wind too soon. I for one am guilty of starting the hardening off process on a day that was too windy for the tender seedlings and also, put them into too much sunlight. I tend to get impatient during the hardening off process...how about you? The next batch is going to go out very gradually, starting out with 15-20 minutes at a time in a partially sunny location and bit by bit, moving into full sun for full days.
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