I hit the post button too early.
My one male leopard flashed at age 2. I have a rescue that is now 4 1/2 years. Looks female, acts like a male and still no idea for sure what he/she is
Not so much a "dated age" helps , but more so the maturity/size of the tortoise as like humans , some mature faster than others- even though have a set age. Most long term breeders can be pretty spot on when the animal itself is in the 6"SCL range. This seems to be the rule of thumb. Although it depends on how many you own/have owned , handled , recorded , the species type within the redfoot group itself.... as there are always surprises .....just like life. There was an excellent thread recently with some good posts from folks as well as a nice illustration. I can tell you that nothing is "concrete" until factors such as "flashing" or the producing of fertile eggs as some adult females will develop concave bellies , wider more V shaped anal scutes, thickened plastron on the rear end - all which are attributes "most of the time " associated with males. It's an experience thing with the more time with the species and studying hatchlings into adulthood. But as mentioned some are very difficult to tell and can rapidly switch what you were positive of sexing. If you take some shots of the tort , there are a few smart and helpful tort folks in here who I'm sure would chime in and help you make a guestimate. Or you may even try soaking your little one in warm water to see if he does flash you - sometimes they will do this. I'm working on a project that may put an end to guessing - and be able to sex right out of the egg.....for all species.
JD~