Just got home from a TA to Southampton England
about day 6 or 7 a bag was left on the bed for wash and fold special $34 being a D+ we get it free.
FWIW I got a bag and my wife got a bag , it is for each D+ in your stateroom . It is limited to stuff like underware, PJ's, socks , tee shirts . A diamond plus member friend put his polo shirts in and they got charged extra for those something like $17 each .
Just beware that your clothes are washed together in VERY HOT water.