I'm going April 18th - 26th and that's looking to be a pretty busy week. I've changed around my Tokyo Dining ADR's so many times and I've never had a problem with different days and just about any time you could want is available. When I first called in the CM didn't even know what Tokyo Dining was, she said "You mean Teppan Edo right?". So it seems like this place isn't very well known yet so you might be OK.