It's interesting you note Yeo Valley because I've found their products very mixed - lots of them do have UPFs. It's interesting that their ice cream doesn't.
There's no Waitrose within 50 miles of me (East Midlands) so Duchy not available. Booja Booja is all dairy free so I wouldn't really consider it ice cream. But in any case it all has coconut oil in it.
Which Yeo Valley products have UPFs? Genuinely interested since that's not my experience. They do put cornflour in their fruit yogurts, but that seems less egregious than most. Their frozen kefir does contain stabilisers.
You shouldn't dismiss Booja Booja. It's nut based and in my opinion excellent. A touch sweet, but a great mouthfeel - less cloying than dairy ice creams, but clearly creamy. The chocolate salted caramel (my favourite) contains no coconut oil. I'm not sure why coconut oil is problematic though.