1) weekly reset on tuesday, 8:00 am GMT

2) and 3) afaik, there is no "per-class" bonus in the duty roulette. there is only a "single complete" bonus, and a "adventurer in need" (which is repeatable at will) bonus. The roulette does reset at JP midnight though

4) only for yourself, but the first time bonus has been changed to a "per class" instead of a "per character" as it was before

5) only guildhest