Do I need to make any Settings changes on my iPhoneX to gain access to Vodafone's 4G Extended network? There are no options to select 4G LTE on my iPhoneX, even though my phone does support this (700MHz). Or do Vodafone need to grant me access first?
4G Extended is just LTE on the L700 Band. If you already have access to LTE (IE you can use LTE in other areas fine) then you don't need to do anything else. Your phone will be able to use L700 in an area where it is deployed..