As indicated in the upfare pricing, there is Z inventory open on flight. The $461.17 price is likely the lowest price point for DTW-LAX as my return LAX-DTW flight only has I bucket open and is pricing at $568.67. $127.93 is likely lowest price point on LAX-SEA as return with I bucket inventory is pricing at $235.43. It looks like they are using married segment inventory as LAX-DTW flight is Z9 standalone, but I4Z0 when married with SEA-LAX flight. For a DTW-MCO roundtrip last month, the lowest seat upgrade price was $278.43 (Z inventory) and highest was $708.43 (with D bucket inventory).