For the international challenge its a UCI event so you would need a UCI license for that. Not sure how you get one in the US, in Canada we dont have a USAC license equivalent so we already use UCI for our licensing (its about $150/year and can be used anywhere in the world generally). As for category, its just elite/jr for this. That said, I dont actually expect too many world class riders to show up, as its right in the middle of worlds and the points would be basically useless to anyone that matters.

Other races, like the 'ontario cup' we have planned in February can be raced under UCI, or under a 1-day permit. Same with all our road events, UCI covers it, otherwise you buy a 1-day (but then you usually can't get points or season standings). Its a big reason why we don't get many US riders here.

the ontario cup races MAY have categories, I have a feeling it will be more like A and B elite, A and B masters, all women. Jr/cadet will have their own races. This year will be lucky to get 1 race in, next winter once panam is over it should be more regular