When do credit cards cashback resets?

Is there a way to find out when do credit cards cashback resets or is it like fixed at the first day of each month?

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Context: I signed up for the DBS Live Fresh credit card (which was activated around 2nd week of October) and already hit the maximum cashback for shopping spending. When can I start using the card to buy more things again in order to maximise the cashback? (1st Nov? or sometime later)