Pulled Brisket
If not left whole, briskets come in two basic cuts. The flat cut (or “first cut”) is less fatty than the “point cut.” However, consider trimming even the flat cut of most of its exterior fat, just so it has about 1/4 inch or so over the meat. The sauce will then have a brighter flavor.
The brisket needs a long time under pressure so that you can shred it, rather than just slice it. That said, it might not even be done with the timing stated. Brisket can be notoriously fussy, becoming tender at various times because of a range of factors well beyond just the size of the meat. If you find you can’t shred the meat easily, put the hunk back in the sauce, bring it back to HIGH pressure, and cook for another 10 minutes, followed again by a natural release.