Not OP but - I can't answer the specific regs, but 16A/240V is absolutely bog standard for the UK and every high street store stocks ovens that will draw this down. They need to be on their own circuit, e.g. this [0].
I've never seen a single oven pull more than this, but devices like [1] are fairly common where you have two independent ovens in one, and it can pull 21A - this would necessitate the 25A supply.
