At 40” tall you should have lots of tomatoes forming and tons of flowers. The discolored leaves is a
nutrient deficiency. Like I said in an earlier post I’ve never grown a tomato plant to fruit using miracle gro. When you start the new
nutrients the plants should get better hopefully it’s not to late.
You should cut the lower leaves up to the first set of tomatoes. Also cut discolored and brown leaves off. I usually pluck the suckers off up to the 3rd - 4th set of tomatoes for large tomatoes. For cherry tomatoes I’ll let the suckers grow above the second set of tomatoes.