My issue is with contract campaigns getting 0% probability. Here is what I see in the log for one of the banners that should be serving:
Creative ID 1332 in zone ID 35 had required impressions of 1, but no delivered impressions:
Aug 23 03:05:57 +0000 OX-maintenance-599cf1119ce39 [ debug] - Calculating remaining operation intervals for ad ID: 1332
Aug 23 03:05:58 +0000 OX-maintenance-599cf1119ce39 [ debug] - Calculating required impressions for ad ID: 1332
Aug 23 03:05:58 +0000 OX-maintenance-599cf1119ce39 [ debug] - Calculating next OI required impressions for ad ID: 1332
Aug 23 03:05:59 +0000 OX-maintenance-599cf1119ce39 [ debug] - Requesting sum of impressions for ad ID 1332 for 5 zones
Aug 23 03:05:59 +0000 OX-maintenance-599cf1119ce39 [ debug] - Creative ID 1332 in zone ID 34 had required impressions of 1, but no delivered impressions: