I posted yesterday on the timing for the announcement. As you'll recall the BOJ does not have a set time
The short version is expect the announcement some time between 0230GMT and 0330 GMT GMT but there is more detail here from my post yesterday:
The announcement may come later in that window (or even after) if discussions sttreth on. The later the announcement the higher the likelihood of some sort of changes afott from the BOJ
I will be back with more ahead of the BOJ, but for an idea of what it is to come I posted previews earlier, here: