One-off shows not marked as such in API

If I understand correctly, the “one_off” field in the API is only marked as true if there is exactly one instance of a non-repeating show. However, on the show’s public page, every instance of a non-repeating show is marked as a One Off (e.g. Is that a known/deliberate discrepancy?

The way I assumed this would work is if a show is non-repeating, it is always considered a one off, but could have multiple instances of one off appearances. But I’ve found that once there are more than one non-repeating time slots on the schedule, the “one_off” field in the API becomes false.

Am I understanding correctly? And if so, is there an alternative approach to my situation that would allow me to have multiple one off occurrences of a show that will all be archived under one show’s public page?