Have you considered it may be the work of a cutworm? I'd be interested to know what varieties of cherry tomatoes you grow and their different characteristics. I grow Sweet 100 for the excellent very sweet taste despite the way it cracks. I tried Super Sweet 100 and they remedied the cracking problem by making a tough skin. I also grew Sungold which was sweet and fruity but not tomatoey enough for me. But I'm open to anything. I like to eat them while harvesting my beefsteaks. I'd also be interested in how the Bush Beefsteak tastes as I've seen reviews of it saying it was insipid while others liked it. Marlynn