The volatility swing is in full action for the Japanese yen right now. USD/JPY saw a very quick drop from around 156.60 to 155.00 before being just as quickly bought back up now to 156.10-20 levels.
It's not immediately clear if this was a first check by Japanese officials. But the size of the drop definitely does invite such a possibility. However, the timing is definitely a little suspect as it comes during a rather active time in markets - also before the US PCE price data later.
If anything, officials tend to look for the most effective and cost-efficient time when intervening. And this is not exactly that.
Either way, the dip is being bought quite strongly and it certainly hints at caution on the kind of risk one might face if you're in any yen trade currently.