Backbend - direction of the upper chest?

Hello

When I do my backbend stretching. In which direction should I press my upper chest?

When I look at pic1 and imagine this position as a position on the floor (like a seal stretch) then the upper chest goes in a different direction as in pic2 (the seal stretch).

It's a little bit confusing

Use the neck position shown in the bottom photo. I prefer to look up slightly higher, arching my neck a little bit more. 

Ok, thank you