Yes pro rata means the cost of the old tariff and the start of the new tariff until the billing date. Everyone pays that for any new upgrade.
Yes you will as we have already explained to you but it will be such a small difference in price, you won't notice it.
Does the phone you want say you pay £50 up front. If yes it's added to your tariff
If no upfront fee then your normal bill will be pence different. @JWF98
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