I hope they do become available.
I was one of the testers for the Bionylons, and they were very fine indeed on a little Loprinzi mahogany soprano... I tried several brands and types of string on that soprano, but the bionylons were perfect for that uke while other strings did not bring out the best in it. I'd really like to have the bionylon option for ukes that would benefit from a mellower string than I usually use. I've found that I'm not much of Worth Brown fan or Ko'olau gold fan or a D'Addario rectified nylon fan, but I do like the bionylons. I also love the Aquila nylguts for most of my ukes, but not for all ukes...
But that's just me... you mileage will probably vary.