The age of the instructor doesn't tell you when they started training. A guy just out of college could have a decade of experience, while the archetype old bearded Asian man could've started last year when his doctor said he should get some exercise.
My TKD school never used the term dan, but you are higher rank than I am.
not sure about TKD but Soo Bahk Do uses the term Dan, I am Sam Dan or 3rd Dan, up to that Cho Dan, Ee Dan then Sam Dan, Sa Dan etc (Sa Dan is also the 1st Master belt)
the only reason I used the term dan is because our school uses the term degree, which appears to not be in use by most other schools so i was just trying to use the term that most people used.
I first started training when i was 6, but have moved and had to start over twice.
Juggernoob, our school doesnt use a junior black belt rank, but im not really even sure what your trying to imply, explain please? or are just being sarcastic for the fun of it? (which i could understand lol)