I have many of these recordings on two Japanese Toshiba "Super Bit Jazz Classics" mini-LP CDs, The Art of Pepper (TOCJ-9311) and Modern Art (TOCJ-9407), which were remastered by Ron McMaster. I'm guessing that, for economic reasons, Mosaic decided to use those remasters after all, rather than have Malcolm Addey remaster the recordings again.
But would that be consistent with the following statement from the Mosaic web site?
"For each of these exceptional sessions, we have returned to the original master tapes and remastered them in 24-bit with greatly improved results from all previous issues. " [bold added]
The McMaster remasters I'm referring to are also in 24-bit, and were done in 2002. But you're right, my guess doesn't seem to be consistent with that statement...
. . . unless they meant to say "improved results from all previous DOMESTIC issues."