Pitcher method in the UK?

Hi all, on this sub there are so many posts about the pitcher method, and it seems to be a really common way to do things in the USA. I’m in the UK, and midwives and the NHS website have both told me not to pre-prepare formula, each bottle must be made fresh. That is what I’m doing, but obviously the pitcher method would be SO much easier!

Why is this method accepted and commonplace in the USA but not recommended in the UK? Is there a difference in our formulas which makes it less safe in the UK, or are recommendations just different?

My baby boy is 6 weeks old and on kendamil, he’s a healthy full term baby.