Hi @Stevo2525
It sounds like you may still be in contract, if you’re wanting to switch to an SIM only plan once this contract is over I’d recommend the same as @andewhite to check the day of/after the contract expiry date.
You’ll be able to make a plan change upwards during your contract, you’ll be able to upgrade to a new device 60 days before the end of your contract and upgrade to a SIM only plan the day your contract expires.
In terms of what you’ll pay you’ll pay at your current tariff price until the point that’s changed, once it’s changed you’ll pay at the new price, the amount will be automatically calculated during that month and if it charges the full amount it’ll correct in the bill after that month.
Tom