It appears that Sola is hungry early in the morning. You might try feeding Sola something just before you go to bed to hold him through the night. Four and a half oz. of food daily is not much for a cat.

As for Sushi, it may be some social problem, or it may be a UTI. Try adding a capsule of d-mannose to the food at each meal. Also, put another litterbox at the opposite end of the house, as this may be due to interaction between the two cats.