When saving a trading contract sometimes you have to check some fields before the contract is released or before you create follow-on documents. For both you can assign separately fields to be checked.
In customizing, under SAP Global Trade Management -> Trading Contracts -> Maintain Schema for Fields to be Checked you can define fields that should be checked before creation of follow-on docuements or releasing. Notice, that selecting Check Release option will lead to status update to M Changed After Release if contract was released before the change.
You can define your own fields check schemas – if you do that don’t forget to assign it to a contract type that you’re using.