Consider a person who lives in location X and has a monthly transit pass which allows them to travel to location Y. That person wants to travel from X to location Z. The transit pass allows them to travel from X to Z but only with the purchase of a supplement ticket. (The price of the supplement is less than the price of a normal ticket that non-monthly pass holders would have to buy.) The person has some questions about the terms and conditions of the supplement ticket. Would such questions be on topic on travel.se?
Yes. Commuting questions are on-topic here, and I see no reason that doesn't include public transit. I can't promise you that anyone here has detailed knowledge of the ticketing rules in a particular region, but by all means, ask away.