If you got a device attached to that plan that has not reached its end contract date FYI you will be charged the remaining amount of the device for the month. That amount will be split up over three payments, over three bills. But you can change your device through online or via webchat or over the phone
... and via the super handy My Optus app:
More > Plan > Change plan ☺️
That's not something we'll be able to assist with here on the forum. You'll need to speak with our support teams online so they can open up your account and advise what options are available to you.
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