Hi @ericaneyy ,
Indeed, you can use a PAC to simultaneous implement the number transfer and cancel the old contract.
You should make sure that the new network provider has good service in the locations where you need it and there are incidents of people needing to immediately take a second PAC so they can leave a new network when it has bad service in their location but they were unaware. Others have accidentally cancelled and lost or put their number at risk of being lost.
As the PAC transfer takes a couple of days to action, realistically, you'll either pay a small early termination charge (should just be the amount you would have paid anyway, not a punitive fine) or might be Direct Debited for a whole month in advance that would need reconciling in the final bill.
You would need to check the terms and conditions for the best timing, hence my convoluted mention of going via PAYG if procrastination is required.
At a guess, the best timing is probably any time after the last bill is raised but before the next bill is raised, the early termination charge should then be the amount unused without any further charge (EE in principle should then partially refund the last month's VAT in the final bill).
https://ee.co.uk/help/help-new/managing-and-using-my-account/leaving-ee/what-is-a-pac-code
