The same code for fetching HKCorrelation (Blood Pressure) on iPhone returns all records, but on watch just 4. Is there a documentation explaining such behavior?
It looks like only records added after installing the app on watch are synced.
The issue was that on iPhone HKHealthStore returns all records, however on watch only records added by release versions of the app are fetched. That's why I didn't see the same data on watch as on iPhone.