Add asterisk before certain paragraph styles. GREP solution?

Hi all

I have the reverse (sort of) for a query I raised a few months ago.

I'm starting to do more and more book interiors and have a requirement to add a scene break (asterisk symbol) before all untabbed paragraphs.

To explain: basically the author had been using untabbed paragraph styles to 'suggest' in-chapter scene breaks, but that 'scene break' now needs to be more obvious. Hence the need to insert a centred asterisk, with its own paragraph style, before all paragraphs that carry an untabbed paragraph style.

To illustrate...

This:

Needs to become this:

I'm embarrassed to say I'm still grappling with GREP for certain things, so any suggestions appreciated.

BTW, if it helps, the paragraph style I have available for targeting are:

Normal-untabbed (for the untabbed paragraph)

Scene Break (for the asterisk paragraph)

There may be an easy answer to this but, today, it's escaping my brain.

Thanks in advance

M