Generally, yes, that is correct. Taxes and fees go up and down. In a few days, the taxes may rise to a higher price than you originally paid. So they generally will not reprice your cruise for a reduction in the taxes.
The future cruise desk only books new reservations, and they can’t change existing ones. If you booked straight with Celebrity, contact them; if you’ve booked with a travel agent contact that agent.
The menu is extensive. It includes all the breakfast foods you would expect to see although is there perhaps something special you want to me to look for?