...So, bad news for Ultra-Act collectors: the line seems to be dead.
(I never managed to grab any myself)
...But, good news for kaiju collectors: the main Figuarts line seems to have picked up the franchise, and with a much more promising monster roster!
Four characters are already out in the wild - original Ultraman, Alien Baltan, Zetton, and Ultraman Zoffy - with several more scheduled for release in 2017, and even more still hinted at.
I have Ultraman(50th anniversary set) and Alien Baltan already, and I look forward to obtaining more!