Currently, the id is the unique field of the event, so looks like there is no easy way to implement the thing you want. The only possible solution for this case is to create two events with different IDs but the same “owner”.
btw, in case if you are using the timeline view - it’s possible to hide some hours from the scale. So you can implement the solution, to remove non-working hours from different dates based on some logic: https://docs.dhtmlx.com/scheduler/custom_scales.html
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