Seeing as many people here were not even aware of planar magnetics until this little e-mail popped up in their inbox, I'd implore you to explore all your options first. Most notable of T50RP mods out there are made by ZMF Headphones and Mr. Speakers, both of whom have now expanded into crafting their own, unique headphone creations. This just seems like a way for Fostex to get rid of all remaining stock of the MKII, hence the "final run" as noted. TLDR: Don't be sheep.
TheTaggerungSounds like someone trying to thin the competition at getting these headphones. Not that you aren't right, depending on how much effort Fostex put into tuning these.
ebjredI own way to many cans already, one of them being a ZMF Vibro MKII. Just wanted to forewarn others about the infectious Massdrop hype. One of my few regrets in this hobby was buying a K7XX before discovering the Sony MA900.