Renew Ads not working after update

I have 3.9 installed on WP3.8 (no sign of 3.9.1 on WP.org yet).

Several sites have expired ads. So I go to the usual ad management screen, mark all of them and do a Renew from the drop-down. The screen refreshes and gives a success message, but the ads are still expired and no dates have changed.

I deactivated and reactivated, no change.

Going into the ad itself and updating the field works, but is an awful lot of clicking on a long list of ads.

Edit: After updating all the ads, the “10 ads expired” message still appears on the main ad management page.

http://wordpress.org/plugins/adrotate/