Is there any reason for Speer to keep the original gold dots around? I can't imagine that these are much more expensive to produce.
Most Gold Dot ammunition is sold to LEA's. Some LEA's may not want to change right away and have to pay more because they are getting good results with the current Gold Dot.
Some LEA's order ammunition 12-18 months in advance so it will take a while to change duty ammunition.
I am sure the new round will cost Speer slightly more to make and they will have to factor in the R&D expenses as well.