Officially (under EU rules that we're still signed up to), it can't be called 'oat milk' on the packaging. That's why Morrisons call it 'oat milk' on their website (so that people wishing to buy it online can find it easily) but 'oat drink' on their cartons:
https://groceries.morrisons.com/products/morrisons-oat-milk-497126011
Do whatever you'd do with cow's milk.
We've been using Waitrose oat version for some time (in addition to cow's milk) and really like it...it foams very well for capuccinos, too.