pictures?

Sure. Here are a couple photos. As beautiful as the flower may be, it just no longer looks like an hibiscus. Very, very strange.

Hope others have an idea of how this switch happened..? Thanks!

Have you ever seen this plant bloom before? i.e., did you buy it out of bloom, trusting a label that said it was a single, but whoops, here's a double? It's gorgeous!

Merkity, not sure if your two pictures are from the same plant but wow (for both)! And Steiconi, I did get this hibiscus when it was in bloom. I selected the best-looking plant of the bunch, which at the time, had beautiful coral flowers (less bright and less orange than what is blooming today). It was definitely flowering singles.. In fact, I didn't even realize Hibiscus can bloom differently and produce these packed-in petals. In all my travels to tropical parts of the world, I've only ever seen the typical, single-flower plant (see Merkity's above). To be honest, I wonder if it's even more than a double? The flowers are quite densely packed together.

So, do you think this is for good? And, how does a plant change its blooming pattern just like that? How often has this happened to others out there? As always, thanks again for all your insight, it's really appreciated!

yes that is the same plant in both pictures. This variety was created by hibiscus lady in Hawaii. it is currently growing in the SF bay area of California. This is likely the first time it has ever had to deal with a northern cal winter..... as it came out of winter dormancy - it started blooming single - as it came back to full growth, the flowers have been returning to their normal double state. you also sometimes see a single flower come out with petaloids - a few extra petals ( but not full double form). I would suspect yours is a double that was showing singles for a bit...stress of any kind can alter the way a plant puts out flowers.