I have been using CJ and receiving checks for more than 2 years. First few months my payments will be sent out only during 20th - 30th of every month. Then after a few months I started getting paid on 19th, then 18th and so on. This month I see that the check has been sent out on 15th!!! As soon as it came from locked status to balance. Perhaps for publishers with good history they make payments faster! When does the payments gets processed for you usually!??
Between the 18th - 21st. I do not think they trust you more or less. Sometimes it falls on weekends and holidays and there can be either a delay or speedup. Actually if you read the TOS it says that the payments are issued on or around the 21st. No exceptions for anyone.