Question 1 is easy:. .. .No. Differences training must be signed off in your logbook by a JAA/CAA FI or CRI. He doesn't have to fly with you and so, if you're already up to speed on it all, he should be happy with a quick groundschool session.. .. .Question 2:. .. .I would say that you still need differences training but, again, this need not be airborne instruction.