We will be sailing on Symphony of the seas this July and I was wondering if I could get some information on formal night. We were on Harmony in 2018 (first cruise in many years) and I was unclear as to what night of the week will be formal night, and what differentiates it from the other nights, is it just attire and the pictures? I must admit it was somewhat confusing to see people dressed very well sitting next to people in shorts.