I don’t understand why the original Jira request was raised. There is no context other than ‘We need’.
The modelling of complex timing is not optimal in openEHR. The modellers have developed a ‘hack’ via archetypes for complex timing over an above DV_DATE_TIME, using a 'Complex timing’SLOT more and more often and nesting a combination of ‘Service direction’ or ‘Therapeutic direction’ alongside ‘Timing-daily’ and ‘Timing non-daily’ to manage most requirements.
When I first spotted the FHIR Timing datatype I have to admit being impressed. They can represent most of what we can, but in a much more straightforward way.
If you want to start to represent ‘Times of the day’, it can’t be done in isolation and should ideally address the whole timing issue so we have a coherent whole. I’d welcome a solution that replaced the complex archetype approach we have now with something more making to the FHIR approach - both for semantic clarity and to make it easier for newbies to model complex timings.
The “Times of the day” value set proposed is one of the least complex aspects of timing.