Why OI / COI changes after market hours?

I have noticed that even after market close at 15:30 hrs, there is a significant change in Open interest and Change in OI figures. Can anyone help me on this, why ?? Is there any after hour adjustment in derrivatives. Attached is for BANK NIFTY Options Chain data.

1 Like

Already answered here

1 Like

Thxa lot @leodecaps.

1 Like