Maybe phosphorus deficiency? Doesn't seem to line up with other pics online.
I fed them twice in short succession, Maybe over feeding? I flushed them out as i thought this was the culprit and I believe they need to be cut down soon.
If not that then too much light... Maybe none of these...
Any ideas?
some info
Planted early May.
Tomato grow bag soil
3 litre plastic pots
fed with miracle grow organic liquid feed slightly diluted down
autos
18/6 under MiGro 100+ 12" away