Dressing for regular and formal night dining seems to be in the eye of the beholder. We sailed the Imagination recently and on a regular night, I did see shorts, jeans and T-shirts. I don't think they turned anyone away. On the formal night, I saw dockers and polos. I wore my military dress uniform and my wife wore a formal gown. When they said formal, we wore formal. We were on a 5-day cruise with one formal night. We took advantage of it.
Have a great cruise.
USAF Cruisers