Hi Orge,
I think people dint get your issue.
If I am getting you right you are asking why dint the SEPM downloaded the Mr4 MP2 packages automatically from liveupdate server.
The answer to this is
yes this is by design. Because to be on MR4 MP2 you first need to be on MR4 only then you can upgarde sucessfully to MR4 MP2.
& this package update comes from the symantec liveupdate server & Symantec has not kept MR4 MP2 packages in the liveupdates because symantec does not know if all the users all over the globe are using version MR4 or not.
I think this answers your question.
Please mark this as solution if it does.:)