Yes. Every time.
You mean "every time", as "always" or the "Yes" meant "Yes, everytime when the 1st and 2nd stairs are not the same model ?"
Because, we are aware of this and, it's an old limitation which we carry over for years, that we cannot have the 1st and 2nd stairs of a different model, for reasons too complex to explain.
We'll see if we could make a check to be sure they'll always be the same model, which is quite realistic in fact, since the 1st and 2nd door or an airplane with 3 stairs in use are usually at the same height, and usually in real life they all look the same on the same parking.
