They are actually Asian Blue Beauties, as they don't originate from Vietnam. Funny little side story.
Anyway, I've had three clutches (on my third this year) of Asian Blue Beauites and it's more about how much you feed your female than temperatures. A few breeders told me this when I first started trying to find information about Blue Beauties and I was a little skeptical, but they were correct.
I'd cut the temperatures to 60-65 for 30 days or so (you can do 90 if you want). I've gotten away with no temperature drop two years in a row, but it might make them friskier faster. Who knows. Anyway, when you warm them up, start feeding them heavily for a few weeks (especially the female) and then introduce them. When introduced, keep up the feeding schedule, until you witness ovulation, etc. Once you know your female is gravid, gradually start slowing their feeding schedule, offering your female smaller meals.
As for size, I can't offer much. I waited until my female was four years and eight foot. Good body weight and proper maturity are the most important thing.
Hope this helps and maybe someone else will have more information. Good luck!
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