Aircraft fuselages being shipped on a boat
The aircraft you saw was N733UK (not Z733UK). It's a Boeing 737-300, most recently operated by European Aviation Group, and before that by easyJet  and bmibaby. It was stored at Bournemouth Airport in 2015 and subsequently dismantled.
This site suggests it's on its way to China to be used for training.
https://www.planespotters.net/airframe/boeing-737-300-n733uk-european-aviation-group/rovlz3