Sorry to hear that Moda,not a UC sufferer but Crohns sufferer and in a flare its murder,especially if its a bad one and you constantly need the loo,i usually take imodium,3tablets before i go out,tend not to eat to much before hand either which eases the loo rushing but lack of fuel for riding is a bugger,
I asked the Gastric nurse about cycling and she said it should be fine,as exercise releases endorphins….i used to feel pretty done in after rides when i was sick,take a few days to recover but since i got an iron infusion i feel way way better during and after rides,
Hope she gets through it ok,