You can simulate an expired advert by setting the advert budget to 0 and the click or impression price to something higher than 0 (0.1 or whatever). Along with the regular setup when an advertiser is linked and involved.
However, due to the small bug I found it won’t show up correctly in the dashboard. The system works, but the dashboard doesn’t show it properly.
I guess nobody bothered to report it, the code has been like this for months 🙁