In SAS® Merchandise Planning 6.8, the source worksheet and all other worksheets that share the same Merch/Loc/Time (MLT) boundaries within other plan versions will be set to What-If when you use the Copy Worksheet function of Copy Dimensions Only. This issue likely occurs when the plan version for the source worksheet was copied and a worksheet with the same MLT boundaries is contained within that copied plan version.
To circumvent this issue, use the worksheet Copy option of Copy and Modify Dimensions and leave the dimensions the same.