Tsukasa is now closed on MONDAYS, not Wednesdays.
The weekend hours for lunch are now 11:30-2:00,
not 12:00 - 2:30.
More importantly, in terms of the quality of the experience at the sushi bar, Ishimoto-san seems to
have gone missing, and Kawasaki-san appears to be training someone new, but he has not graduated him to chef yet. If you have been to Tsukasa, Kawasaki-san prepares the orders of the tables as well as his section of the bar. He is now overwhelmed. The quality of the fish is still very high, but service at the bar is glacial and the nice touches are gone due to time pressure. Yesterday, some groups just left the bar - very impolitely for Japanese couples.
I don't speak Japanese, but there must be some way to politely inquire about the fate of Ishimoto-san (and more generally, the problem: he needs to close several tables and/or remove half the seats at the bar until he has the workforce to handle the operation.) Of course, if Ishimoto-san is on vacation or training in Japan, these measures can be temporary. Otherwise I fear that the future of Tsukasa is not promising. :-(