Examine search's RangeQuery<DateTime> not returning any results

Questions
1

Umbraco 10

I am trying to use a RangeQuery with DateTime range eg.

searchQuery = searcher
                            .CreateQuery(searcherSettings.IndexingType)
                            .NativeQuery($"+__IndexType:{IndexTypes.Content} +__NodeTypeAlias:{searcherSettings.ContentTypeToSearch.GetDescription()} ");

and then date range option:

   if (searcherSettings.DateRangeProperties != null && searcherSettings.DateRangeProperties.Any())
                    {
                        foreach (var item in searcherSettings.DateRangeProperties)
                        {
                            searchQuery = searchQuery.And().RangeQuery<DateTime>(
                              new[] { item.PropertyName },
                              item.StartDate,
                              item.EndDate,
                              minInclusive: true,
                              maxInclusive: true);
                        }
                    }

The query ultimately resolves to:

Category: “content”, LuceneQuery: {+(+__IndexType:content
+__NodeTypeAlias:booking) +(startDate:[637397856000000000 TO 638092512000000000])}

Despite there are plenty of records between those dates (2 years) - it is not returning any results.
If I remove the date range condition - it returns all results as expected.

I am using a NativeQuery above but without it also has the same effect:

searchQuery = searcher.CreateQuery(searcherSettings.IndexingType)
.Field("__NodeTypeAlias", searcherSettings.ContentTypeToSearch.GetDescription());

If I try to use a raw query like this:

searchQuery = searcher
                            .CreateQuery()
                            .NativeQuery($"+__IndexType:{IndexTypes.Content} +__NodeTypeAlias:{searcherSettings.ContentTypeToSearch.GetDescription()} {searcherSettings.RawQuery} -umbracoNaviHide:1 ");

where searcherSettings.RawQuery is a string:

"+(startDate:[637397856000000000 TO 638092512000000000])"

the searchQuery resolves to

Category: null, LuceneQuery: {+(+__IndexType:content +__NodeTypeAlias:booking +startDate:[* TO *] -umbracoNaviHide:1)}

What is going on here?

This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/110864-examine-searchs-rangequerydatetime-not-returning-any-results