“It’s draft hasn’t change”
MT a tank, refill with sea water. I did it. Its called ballast.
Tankers also have segregated ballast tanks they can fill as they discharge the oil (into lighters). They wouldn’t have to fill cargo tanks till their ballast tanks are full. They could discharge their entire cargo without a change in draft.
The ship may end up sailing away with the same draft someday, MT of all cargo.
The tanker owners want their ship back in service too.