I believe in the science of how contrails are formed, but, the sun is strong and it is being deliberately covered. The conditions in the atmosphere play a role in contrail formation, however, the conditions cannot always be there for when the sun trailing is necessary and I believe there are additives to cause the contrails to last endlessly and turn into clouds. Observing too many planes in the sky at one time....working as a team and flying low. Just my thoughts. The sky is too radically full of these trails and a lot of the scientific explanation doesn't always add up. Over simplification perhaps.