I have planning to MNP to hotlink flex, currently work at SG, may i know about the bank TAC sms on roaming (without data internet), need only receive the TAC from bank when doing bank transaction. Receive this TAC sms got any charges when abroad?

If i starting choose the flex 30, can i upgrade to flex 40? how long period can change?

Unlimited call/sms to all network? 1800 and 03-xxx , got charges?

Monthly data depleted, any topup data options buy add-on?