I recently wrote up draft of temporal uri scheme rfc.
It is rather simple ... for example, given the URI:
Would represent a discrete point in time of "2022-12-22T16:28:13Z".
This rfc is just about the 'minting' of date-time identifiers eg. it is possible to create two identifiers that represent that same point in time ... which is left for others and OWA to consider ;)
The idea is that when creating triples (in the semantic sense) often it would be useful to define time as a subject.
<dt:1985-12-25T23:20:50.52Z> somens:hadEvent xmas:celebration