NX SB Flat Solid is not in the same time stamp order in NX2206 as in NX12.

In NX12, when you create a new feature after Straight Brake (SB) Flat Solid, the SB Flat Solid is at the bottom of the PNT.

In NX2206, when you create a new feature after SB Flat Solid, the new feature is at the bottom of the PNT.

Before creating Offset Region in NX12:

In NX2206:

Observe that the 'Offset Region' appears below 'Flat Solid' feature in Model History instead of Model History being reordered as expected.

In NX2206, Flat Solid Settings has "Fix at Current Timestamp" ON as default during creation which causes Flat Solid to stay at the same order.

If you toggle "Fix at Current Timestamp" off when Flat Solid is created, you will get the same behavior as NX12.

Note: If you create Flat Solid with "Fix at Current Timestamp" ON, you cannot toggle it off later.