For my case no. I was short in my income requirement too but they approved my application.

WRONG , it is BASE ON STATEMENT AMOUNT.
So if you have spent RM 1000 in Petronas + RM 500 in Groceries,
Your statement amount will be RM 1000

Cashback on next statement : RM 60 on Petronas + RM 15 on Groceries

So next statement starts with negative RM 75
you need to spend at least RM 1575 to eligible for the cashback

DO NOT REPEAT MY ERROR.
i lost RM 60 due to this 

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For Petronas Visa Platinum, you will be saved coz most of the peeps will spent RM 1250 on Petronas, and the min state amount is RM 500 , so just do RM 1250 per month will do