Contract Header Information
Specifying Contract Effectivity and Maximum Duration: You can specify the dates that your contract is effective. The dates you enter become the default dates for each new contract line and set a limit to the duration of all lines in the contract.
A contract line cannot have a start date earlier than the contract header start date or an end date later than the contract header end date. Entering effectivity dates using this procedure affects new lines only. To make the new dates also apply to existing contract lines, you must cascade the values to those lines.
You can change the dates that you specify here at the individual line or subline level provided the changes do not fall outside this range.