Don't cut them. As I see your tomatoes have lots of suckers so they are not growing in a linear mode, the bigger they grow the exceedingly more nutrient they need. If something runs short from the soil, they start pulling from the old leaves to feed the growing tips and fruits. This mottled leaves are rare to see and it took me a while to figure out. For diagnosis purpose, I fixed it with molybdenum alone. You can try wood ash in water for quick mineral recharge, as high pH makes Mo more available. In the future, adding basalt rock dust, alfalfa meal, rabbit manure or worm castings will make the soil rich and balanced.
