How to return ALL facets if there are more than 1000

I have property that is defined as a stringFacet and it has more than 1000 unique values. When requesting facets the max number for numBuckets is 1000.

How can I get the remaining facets? Why is there such a limitation?

And how can I know in the if there are facets that have not been returned? e.g. do I have exactly 1000 entries, or there are still some that were not returned?

anyone from the mongo team that can help?