You can , top right corner, press 3 dots, then choose edit week, then change whatever you want, even week number, not only type. No need to delete anything.
You can remove a week and start over .hit the .... upper right corner of screen then scroll down remove week is there .on and Android phone its that way anyhow .I had hardest time finding were to put harvest stuff before cause I wasn't scrolling down that menu in corner