I posted on this earlier but ICYMI, Tokyo area inflation data for December is due at 2330 GMT.

Economic calendar in Asia 10 January 2023 22

Earlier:

The Tokyo CPI data is used as an indicator (an imperfect one) to National CPI, which is due in around 3 weeks.

Take note that:

Core-core inflation is the CPI excluding Food, Energy. This is the closest of the Japanese CPI measures to the US core CPI.

Coming up in April, or after, will be a long, hard look at the BOJ mandate:

A new agreement between Japan's government and the Bank of Japan would pave the way for a dilution of the current ultra-easy BOJ and would be supportive of the yen at the margin. The yen has already strengthened since its October 2022 low as the market looks ahead to a 'pivot' from the BOJ (it'll be small, but any scaling back of ultra-easy policy from the Bank of Japan is notable).