Returned search results not always respecting sort order

Hi. I have `helm-org-rifle-sort-order` set to `nil`, which I believe corresponds to the order that the result occurs in the buffer.

I have an org file that is ~30K lines long. I am executing `helm-org-rifle`, entering a search term, then entering follow mode with `C-c` `C-f`.

The first search result is found at line 124. The next is at 208, then the results appear to be in buffer order up to the one at line 18014. However the ones after this, respectively, are on lines 126, 133, 136 and 196.

Just wondering what the cause of this might be, fully recognising that the problem may lie with the operator.