Bret,
I doubt they will change anything that creates a different exterior appearance. The whole reason for this engine is that they were mad that none of the locomotives in this class were saved, so they built the "next" one. I also understand that much of the fundraising has been done by subscription.
The UK (and many other countries) value their history far more than we do. If you don't have at least four operable steam locomotives (and under steam at the same time), you are one of the smaller or poorer groups. Too bad there isn't the same interest over here.
Maybe instead of the 252 and 253, start with a smaller project? Climax? #51?