I don't know. I can ask Andre if you need to know.
If this is a real title the author is probably Norton/Sherwood Smith. I've started an E-mail dialog with her, and could check this title.
A few years ago TOR proposed continuations of the SOLAR QUEEN series and the CROSSTIME AGENT series.
I haven't seen this title listed in either Locus or SF Chronicle, so my be is still that Books in Print is wrong.

Can you E-mail me the entire Books in Print citation? Please include Publisher & ISBN if given.