My petition was approved in April this year under [b]H1B cap-exempt quota[/b]. For my receipt number the USCIS site http://www.uscis.gov/portal/site/uscis still shows TAB as "DECISION" & not "POST DECISION ACTIVITY". What is the difference between the two? When will my status change to "POST DECISION ACTIVITY". Is it something to worry about? My petition shows start date as first week of April 2013.