Software Update in ICS 4.0 for neo

Hi,

I updated my neo to ICS 4.0 , Build Number is 4.1.A.0.562 . But looking at the Sony's Android 4.0 page. It shows the latest available software is 4.1.B.0.587.

When I connect the phone to Sony's PC Companion, it says that my software is up to date. Why is this happening? How can I update my software? Will I have to do it manually from the Sony's site?

Kindly give your suggestions.

Thanks.