see for example contribution tracking id 39012241 in payments-adyen from 10/25, all on payments1001. They get to our site at 10:04:16, open the iframe at 10:04:56 and get redirected back from the CC processor at 10:07:28. Unfortunately their session is dead - Resultswitcher: 39012241.0 SHOULD BE FORBIDDEN. Reason: No active donation in the session - and they get a new ct_id 39012552.
39048372.0 on payments1003 had a session die between requests at 20:19:42 and 20:24:09.
39037084.1 on payments1002 died between 16:54:37 and 16:56:50