The first paragraph of the NTSB statement:
--
This is preliminary information, subject to change, and may contain
errors. Any errors in this report will be corrected when the final
report has been completed.
--
It will be weeks or months before they produce conclusions. The report
we are seeing is a summary of the facts as they know them at the time
of initial investigation.

Unfortunately, the NTSB generaly only puts out two reports. The
original, usually very sketchy, and the final, factual one. In
between, we just wait.

-Tom