I hate to say it, but it is blight. All of my outside grown tomatoes were having that, it damage the plant very fast with out touching the leaves ( only severe patches on the stems) and then it goes to the fruit too and it spead very fast too. You will see the domino effect where it infect one plant to the other ( if the toms were planted in raw ).
My japanese black trifele and the black cherrie were among the last who gets it. Destroy them and remove all the infected plant parts.

Momol

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