FYI. someone training with you can be certified in 12 months and become an instructor under you in another 8 to 12 months, it just depends on how well they grasp the material.
Besides the simplicity of the SDTS, the certification is based on how well you understand the curriculum not how long you’ve trained. Come exam day you either know it or you don’t. It’s up to you to get your ass to class and prepare. Who the hell am I to tell you how long its going to take to learn this stuff? Seriously, if you know it, no one should get in your way.