I had a period of heavy rain and humid air and my tomatoes have been getting progressively worse (i live in zone 7b). I think it early blight, I have attached photos. I'm growing better, big boy, Rutgers, lemon boy, brandy wine, and goliath. They are all in grow bags expect for small patch, and the ones in the ground aren't really that affected, some minor discoloration on the bottom leaves (i have pulled those off).

I should also mention the ones in the ground are flowering and the ones in the bags are approaching flower as well. Some of the ones are already displaying yellow flowers. I'm trying to grow organically so I have used baking soda, organic soap, and water to attempt to rectify the possible early blight situation. I figured changing the ph of the leaves would help stop the spread.

How should I go about keeping the possible early blight at bay? I know that the spores remain in the soil, so it's hard to completely eradicate. A local member of my community suggested killing all the affected plants and taking them off the property immediately or burning them. I really don't really want to do that because I have 96 plants that are currently affected.

Any help would be great, and sorry for the long post, I'm trying to provide lots of details.