Could the yellow seeds have been reds mixed in, but not appear red
Your post is a little hard to follow when you switch between the words seed and true seed.
TPS - are seeds harvested from the tomato like fruit on top.
Seed potato - Are tubers harvested below the plant and used for cloning.
Tubers, as far as I know, clone identical tubers.
TPS, have 16 variations or more.
I have a feeling you missed red potatoes in both areas and for some reason all the yellows in the late bed rotted, didn't germinate.
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