The change order tier setting configured for the Prime Contracts tool only affects the number of tiers used for the overall change management process. An owner can always be marked as a designated 'Reviewer' on a PCCO when you want it to be approved by an owner. To learn how to approve a PCCO as an owner, see Approve or Reject Prime Contract Change Orders (PCCOs).
If your project is configured for 2-tier or 3-tier change orders and your project team wants an owner to review change order information at an earlier point in the overall change management process, you can email a Potential Change Order (PCO) or Change Order Request (COR) to an owner. For instructions see the links below:
When configuring the number of prime contract change order (PCCO) tiers for the Prime Contracts tool, a user with 'Admin' permission on the tool can choose between a 1-tier, 2-tier-, or 3-tier configuration. See What are the different change order tiers?