Sushi Dai after tuna auction – possible?

We're heading to the tuna auction on Tuesday, and I'm wondering if anyone has experience of hitting Sushi Dai afterward? If we're there for about 6.30am, is it possible to be served? (I know there will be a huge queue.) Or is it better to go really early and queue at Dai for a reservation spot beforehand? (If that's possible?) Any advice appreciated!

by snedface