is that showing only preflower at nodes or do you see pistils developing at terminal and axillary buds?
if so, just slow AF auto, i guess.. possibly environment? genetics?...
otherwise if just leafy (can't tell in pics for certain), it may just be a photopeiod... at 10 weeks... photos can show preflowers at nodes in vege. .. sometimes it's a seed mix up, sometimes it's pollen contamination, sometimes it's poor breeding practices, but you can get an "auto" that clear is not an auto occasionally.. should be a rare thing.
got a 2nd light? try giving it 12/12 and isolate it until end... again, only if you do not see pistil development outside of preflowers at gowth nodes. if you do, it's finally going into flower.