Can I dig these up and re plant?

Please see the pic.  Those are broad beans coming up right next to each other because I planted them in twos in case one didn't take.

I want 2 rows of nine and as you can see they're coming up well.  There's just one gap where nothing's come up yet.  When's the right time to transplant one of the spares to fill the gap?  Is it now before the roots get too big and tangled up with each other or later when they're a bit stronger and less prone to injury with my hand fork?

Thanks 240173paul that's a good tip for the future which I'll definately do next time.  Ta