Security Check on Premium H 1

[lovely123]

Hello,

I filed change of status (h4 to h1) on 10/28 under premium processing and the case has been updated as case received and pending on 10/29.
Since then it has the same status. My employer contacted to USCIS and he has been told that the petition has been picked for security check and now it will go under normal processing. And the $ 1000 will be returned with final decision/approval.

Any idea what is security check and why? How long it will take now?

Thanks.

[txh1b]

Could be any reason. Your name, your job, your background. No one can tell.