First, Were the plants transplanted from outdoors to indoor pots or were they already in pots outside?
Second, If they were transplanted, was it during the flowering stage? How far along are the plants?
If the plants were transplanted, especially late in flowering in can cause the plant A LOT of stress.
One more thing to note, when cannbis plants are in the flowering stage they draw A LOT of energy from the the plant to produce those big juicy buds. In turn, the leaves at the lower end of the plant will yellow and die off due to lack of proper light and being sucked dry of nutrients from your greedy buds.
In the pictures it is hard to see what your exactly talking about so i am going off prior experience and trying to visualize to help you out.
Hope i was some help, let me know if you have any questions.
