If your studio is taking about “making a switch to HTML5” I think their mindset is seriously flawed. In some cases HTML5 open web technologies are better, and in some cases Flash technologies are better. It has been like that for years and years, and will continue to be like that. To just stop doing one in favor of completely “switching” to the other is just a silly approach.
Having said that, I’ll try to answer your question.
Away3D only exists for Flash, so if Flash was to hypothetically go away you would not be able to use it in any other technology. However, I have absolutely no reason to believe that Flash will be going away in the next several years. Adobe is investing heavily in the desktop browser player and in AIR for mobile, and there are several game studios and other companies that are still conducting large-scale, long-term development for the platform. There are some things that simply can’t be done as reliably and with as much reach in the open web technologies as it can with Flash, and real-time 3D is one of those things. WebGL will probably never come to Internet Explorer, so even if it continues to grow at the current pace it will never reach the kind of market penetration that Flash has.
Besides, if you have spent 8 months learning Away3D, you have most likely been learning a lot more than just the Away3D API, such as general 3D concepts, approaches and solutions. Those apply to any 3D technology. So if you were to switch to building native mobile apps, or using WebGL and javascript, a lot of your newfound knowledge would translate.
And there is nothing saying that there will never be an Away3D for other languages. We tried once with HaXe, but never got the sort of traction that motivated continued development. Maybe we’ll try again with some other language at some point, and if the demand is there, development will likely continue in parallel with the standard Flash version of Away3D.