Y2K fixes for ProDOS, GSOS and Basic.System:

These are real Y2K bugs of the "2 digit variety". These files were
made in the 1990's so even as late as that programmers were inducing
Y2K bugs of this type.  These bugs account for some reported bugs in
ProSel which were not, in fact, bugs. These fixes will take care of
them (but of course there are a lot of other programs out there and
it may affect some in undesirable ways).
All these bugs essentially converted 20xx dates to 19xx dates.

File P8 in the System directory or ProDOS on 8 bit systems:

Find $c9 64 90 04
Change the $90 to $80
(in version 2.0.3 it is at relative byte $FB3)
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File Pro.FST in the System/FSTS directory:

Find $c9 64 00 90 03
Change the $90 to $80
(in my version it is at relative byte $B41)
----------
File Basic.System wherever it may be hiding:

Find $c9 64 90 12
Change the $90 to $80
(in version 1.5 it is at relative byte $FAF)

Glen Bredon