It depends, if it's GIRO will only processed during working days and IBFT will be instantly.
FYI, from 01 Oct till 31 Dec, IBFT to other banks is free of charge. Please fully utilize this free period.

So that means that you cannot use your cash back to offset your statement amount.

But, the weird thing is that the finance charges is at RM 18.19 which translates to
RM 1455+- spending with 1.25% per month finance charges
RM 1280+- spending with 1.42% per month finance charges
RM 1212+- spending with 1.5% per month finance charges

none of my balance falls into that. 

Another thing to note is that my August statement, I paid amount after deducting cash rebate also don't have finance charges.

8. The Cash Rebates earned by the Cardholder for each current month
will be calculated (rounded to the nearest Malaysian Ringgit) up until
the statement date (as specified under Clause 9 below) in respect
of the said current month and will be posted to the Cardholder’s
Cash Rebate Card account in the next month’s statement date.
The Cash Rebate earned shall be utilized towards payment of the
outstanding balances due on the Cardholder’s Cash Rebate Card
account with the exception of Cash Rebate earned under the “10%
Cash Rebate on Finance Charges” charged, which shall only be used
towards payment of the finance charges charged by CIMB.

A finance charge will be levied on your unpaid outstanding balance and all new transactions from the date the transactions are posted.
But I have 0 outstanding balance.

Still doesn't make sense here.