Diff regular vs Premium

What is the difference between “case approved” and " case was approved and my decession was emailed".

How do I know, any case is approved today is regular or Premium.? Is it only employer has to tell or any other way to know these details.

“case was approved and my decision was emailed” is an update for premium processing.For more details, read this:http://redbus2us.com/uscis-online-h1b-case-status-meaning-detailed-screenshots-changes-flow/