How do you report hours that vary week to week? - 17 weeks in

I work some days through a staffing agency while still certifying. I am in Knoxville, in case local advice matters. The form asks for gross earnings, which I do not see until later. Did anyone get an overpayment notice from a mistake?

Thanks for writing this out. I went through something close to it last year, and it got easier once I kept a simple log of every call and form.