Master the Mainframe – Finished?

Got email “Congratulations on completing Part 3! You have made your way to the end of the Learning System challenges”. I don’t think I really am finished. Was working on the final challenge. Through out course it was said it’s not a race. Also I wanted to go back and check my answers because as I said at one point I reran a previous task (because I suspected a problem) which failed (proving there was a problem) causing the completed task to be overwritten and appear incomplete. So I was taking my time and had plans for the last task. They did say there are no wrong answers and I did have something basic testing stuff there, but it was meant to build on.