@Grantbreezy
If buying through a 3rd party you would need to pay off what you owe on the sim only plan.
If you upgrade directly with O2 the fee will be waived.
You need to work out which is the cheapest overall for you.
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
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