Tomorrow, the Cardinals must submit their 40 man roster. The 40 man will mostly remain the same as it was on September 30th. The exceptions are players whose six years of service with the Cardinals ran out and entered free agency. They need to add Rule 5 eligible players by tomorrow, or they will be exposed to the Rule 5 draft. Right now, the 40 man roster is at 38 players.
There is, to my eye, really one guy who is danger of being removed from the 40 man roster: Dominic Leone. Leone is arbitration eligible and is set to make a grand total of $1.