Switching one meal day for another

I would like to know if it is possible to switch, say; Sundays meal for Saturday. Due to busier days during the week, I would like to have the option of switching a more complicated meal on a certain day with a less complicated one. If I try to edit one particular day on my weekly menu, to reflect another particular day on the same weeks menu, I do not have the same options when trying to switch the menu one food item for another food item…the lists on each day are different. I understand we are tying to stay with certain food combinations on certain days, just hoping to make some more interesting meals on the days that I have time to do so.