"What" instead of "which"

I have noticed that the use of the word “what” instead of “which” seems to becoming more prevalent in the U.K for certain contexts. For example “What train do we need to catch” instead of “Which train…”

Surely this isn’t right? When referring to an object (i.e. not a person), the word “which” should be used.

<,Surely this isn’t right? When referring to an object (i.e. not a person), the word “which” should be used. >>

I would think it was the other way around: 'what' for object; 'which' for person, but just my viewpoint.

To me either is fine, but the two variations do not 100% equate in my mind, i.e. they don't mean exactly the same thing.

'which' implying a decision between two or more.
'what' meaning "what kind of"

but I will admit, in the context you pose it above, 'what' does seem odd.