I filled out the 2021 forms when I meant to fill out the 2024 forms, but when I changed 2021 to 2024, I lost all of my work. (When I say "lost," I was able to re-obtain it by switching back to 2021, but this is still undesirable.)

If the year is so instrumental to the forms, I think it needs to go in a modal that you must fill in before filling in any other forms.