Is anyone using schema.org markup for library hours?

We have our address marked up and google shows a "knowledge graph/card" when you search "hatfield library", and I'd love to be able to include the hours but am worried about accuracy - I have no idea how often google checks / updates this data, and it looks like the "valid through" property can't be applied to hours.   I'd love to hear from a library trying this.




I did find one example of a knowledge card with hours, but didn't see markup on their page (anyone from OSU care to enlighten me?)