Hm, this is a bit weird ... if they want to do it right (and I'm sure they want!), why not postpone it, even if by some years (okay, the future isn't safe, I guess, but ...), and wait for the metal parts to become accessible again? Or does such stuff take decades with the LoC?
I'm not sure I'll get this, it's one I'd rather jump for at the last moment, I guess, if at all ... the Ella sides, master takes only, are covered in the French Complete Masters box, for Webb I've got Chronos which probably can't complete with other releases soundwise, but still, I guess I've got 90% of the music and this isn't exactly a cheap set, so ...
Seems, btw, to be 49 tracks taken from CDs (my browser gives 53 hits for "(CD)", four in the discography, the rest in the list of sources used - btw. those lists are a nice idea, play it open, I sure appreciate that! And I wonder how often in earlier sets they actually might have done the same, might have even announced it in the "producer's note", but it's somewhat hidden in there, the detailed list is a nice new addition, I've only seen it once in a box, I think .. is there on in the Hines? A friend got this and I was there when he opened it, don't have it myself yet.)