KOMA-Script Report Class: cannot select biblatex

[Rich Shepard]

I had a similar issue last June but there no longer are old, deprecated,
font style commands in my jabrefbib.bib file. I searched my lyx mail file
(from 2005) without seeing this particular situation.

I've created a new KOMA-Script report class MWE (attached.) It has only a
title and the question, "Why can't I change the bibliograpy style format in
Document -> Settings -> Bibliography?"

The style format data entry box has greyed out 'Natbib (BibTex)' and there
are no other choices available.

What do I do to fix this so I can select BibLaTeX as the style format (and
related style choices?)

TIA,

Rich
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#LyX 2.3 created this file. For more info see http://www.lyx.org/
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\makeatletter
\@addtoreset{figure}{subsection}% Reset figure numbering at every part
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natbibapa
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\begin_body

\begin_layout Title
Minimal Wrong Example: KOMA-Script Report Class Bibliography
\end_layout

\begin_layout Standard
Why can't I change the style format to biblatex?
\end_layout

\end_body
\end_document