You do not need to wait for your contract to expire before upgrading to fibre. Upgrading will start you on a new contract anyway. If you do let your broadband go out of contract first, nothing happens to your service, you are then on a monthly rolling service and be subject to any package price changes.
I am not employed by TalkTalk, I'm just a customer. If my post has fixed the issue, please mark it as the Best Answer.
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