Irregular split is to set a net value, and the fund will split when it reaches the net value.
Because all the graded funds have been established for a long time, they are split regularly, and there is no such thing as not splitting. However, regular splitting is mainly aimed at A-level shares, and most B-level shares are split irregularly.
Many B-level shares have not been split irregularly because their net value has not reached the set net value.