Keep in mind that PB1 was a full installer, and PB1 and DP4 were fairly close in build numbers. Updating with the DP5 delta installer should have updated the necessary components.
Installing a delta DP6 over PB1 might not update a component that was previously updated in DP5 (hence the nature of delta vs combo/full installers)
Well that is critical information. Thank you for that. So if I understand correctly, you are saying that If I am on PB1, I must update to DP5 then update to DP6. Is that the only way to go if I want to get on DP6? It's looking that way, unless there is a combo/full installer that will become available.