You should be able to do that just now. Create the board first (I.e DB-02), then go back to DB-01 and right click on the circuit and select Feed Distribution Board...

I think it would be a good idea to have that Feed Distribution Board... even if you don't have the targeted distribution board created, since you can already create a new board from the modal triggered.

Will slightly tweak the behaviour so you can use the Feed DB without creating the board.

Other than that, this should work as it is just now.