Reporting part-time earnings while on benefits

I work some days through a staffing agency while still certifying. I have read a lot of threads here and could not find my exact situation. Sometimes my paycheck is late by a week. Do you report when you earned it or when you were paid?

I estimated and then checked my pay stub. When there was a small difference I wrote to the agency to correct it.

Keep everything in writing and save the confirmation numbers. It made the follow-up calls so much easier.