Only two years, seriously? Based on the USAF hours requirements, going from shodan to nidan is 600 days minimum -- just barely doable if you train pretty much every day of those two years. More realistically, given the availability of classes and life requirements, I figure a fairly committed student might -- might do 200 days of training (averaging 4 days a week) in a year. Has anyone who wasn't an uchideshi gone from shodan to nidan in a two-year timeframe?
I'm going from memory (risky at my age) but minimum reqs (CAA) are 2 years and 540 training days. Lucky for us there are classes 6 days a week (Sunday is free practice) 13 hours + kids classes. Sensei knows when readiness has occurred.
I always figured 'committed' = uchideshi. I'm just a dilettant. I do know of a few folks that went to nidan in 2 years without a stint as uchideshi.