I believe the TH is now out of production. It certainly doesn't appear on the Yuneec UK web site any more. There are still some TH's to be had from dealers that still have stock so anyone wanting to buy a TH won't have too much trouble finding one but, of course, that won't last forever.
There does seem to be a shortage of Power 4 batteries. Speaking as a U.K. resident, they are impossible to source in the U.K. at the moment. Indeed, many third party batteries are becoming hard to come by, at least in the U.K. However, Gifi 8050mAh batteries are easy to get so long as you are prepared for long delivery times from China (I received one yesterday that I ordered on the 20th Aug, but I consider myself lucky to have received it so fast).
As alluded to above, Certain parts are no longer stocked by dealers. To meet any repair challenges, more and more people are buying crashed TH's to cannibalize for spares.
All of the above, then, raises concern for those buying new TH's from dealers who still have them in stock. If I were to be looking for a new drone I would not consider a TH. Not because there's anything wrong with them...after all, I'm quite happy with mine, it's just the hardness to get parts and unmodified batteries that is making the platform obsolete (probably an intended business strategy on Yuneec's part).