I currently hold a UK short term tourist visa. Recently we have decided to marry with my partner (who lives in UK), who I've been together with for 5 years. For us to register the marriage in UK I need a marriage visitorMarriage Visitor visa, aka fiancealso known as fiancé visa. My tourist visa expires in March, but we'd like to get married earlier, in January.
Is it possible to switch from tourist visa to the fiancefiancé one before the tourist one expires?