Validity dates of APO orders

Hello Experts,

Request your help here.

My PDS validity date is till 9999 , but the validity of all planned orders and process orders in APO are only till 2037.

Calenders and time streams are maintained till 2025

What is the reason for the same and how is the validity of orders generated?

And one of the order is having validity date as 2017 (past) due to some manual changes in some operation confirmations.

Is there a way to change the validity of the orders?

Regards,

Prash