If a date report with no instances has a date filter applied that relates to the report field (e.g. startDate filter for startDate report), then instead of returning an empty result, the report returns one or more empty buckets. For consistency, we should always return empty results when there are no instances in the report.
This behaviour seems similar to
OPT-3910 and could be the same issue. I've also attached a screenshot with an example IT test case that reproduces the issue - the shown test passes for running and end date reports but not for start date reports.
- all date reports return an empty result if there are no instances in the report, even when filters have been applied