Personalise Safari windows with different pins?

Hi, all.

This is my first post so I hope I'm following the correct protocol.

Basically, I was wondering whether the new pinned tabs function for El Capitan allows users to open windows with different tabs for different uses? For example:

First window: BBC, Guardian, New York Times, Reuters (News)

Second window: Behance, Dribbble, Fonts In Use, Creative Boom (Design)

Third window: Product Hunt, TechCrunch, The Next Web, Mashable (Tech etc.)

Or whether the same tabs have to / will be opened up with every new window launch?

Cheers,

Celeryshed