Let's just hope it was a case of bad luck then I tried too but I'm usually jinxed, and the fact that not knowing when exactly Jane played the role doesn't help much, I found the Carmen Duncan episodes so much more easily
Rosemary Prinz did NOT appear on the show in 1979. IMDB is often wrong and poorly maintained. Bob gets a phone call from Penny, whom we do not see. He then leaves for a while. I imagine this may have been a story the interim writers set up that the Dobsons dropped, as it was more interesting to have a pornstache weirdo dominate the canvas.
There is some talk about the recast Penny earlier in the thread. Most of us never saw her.
I don't watch BB anymore, although I still follow along to a point, but my main takeaway is how offputting it is to have a host pushing their religious views so heavily into the narrative (and I think she now also sends all the contestants Bibles...).
I tried hunting down some episodes with Jane Powell. But i couldn't find any. I'm usually pretty good at hunting down stuff. Maybe another poster might have better luck than i did. Or maybe there aren't any episodes with JP filling in as Lisa.