Hi Monty,
That's a great question and I'll tell you how I know this. The Sire, or father, of the 05 clutch went through his Pastel Change at 3 years of age, about 3 years ago. And he has never changed back. The change is permanent. We kept all of the 05 babies from that clutch the moment we saw the father change into a pastel beauty and we have been waiting 3 years for the offspring to change and now all but 2 have gone through this incredible change. Up until this point in time the "Pastel Ceylonese" was really just a theory, a sacred hope and I guess a real long-shot. I know there are a LOT of happy customers that bought them while they were still cheap and a lot of upset folks that passed on them, lol.
There is a more detailed account of the story behind these on our website on the Ceylonese Page. Here's the link:
http://highendherps.com/wst_page12.html
Have a great day.