> Report KPIs for each shift. Shifts start at 8:00 local time.

To represent this you probably don't want a local date. Plain times [1] and plain date/times [2] are a better fit.

[1]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

[2]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...