question about asia/baku 1992

[Olson, Arthur David (NIH/NCI)]

This partial output from "zdump -v Asia/Baku" indicates that there is indeed
something peculiar happening around 1991 and 1992;
does anyone know if the output reflects reality?

				--ado

...
Asia/Baku  Sat Mar 24 21:59:59 1990 UTC = Sun Mar 25 01:59:59 1990 BAKT
isdst=0
Asia/Baku  Sat Mar 24 22:00:00 1990 UTC = Sun Mar 25 03:00:00 1990 BAKST
isdst=1
Asia/Baku  Sat Sep 29 21:59:59 1990 UTC = Sun Sep 30 02:59:59 1990 BAKST
isdst=1
Asia/Baku  Sat Sep 29 22:00:00 1990 UTC = Sun Sep 30 02:00:00 1990 BAKT
isdst=0
Asia/Baku  Sat Mar 30 21:59:59 1991 UTC = Sun Mar 31 01:59:59 1991 BAKT
isdst=0
Asia/Baku  Sat Mar 30 22:00:00 1991 UTC = Sun Mar 31 02:00:00 1991 BAKST
isdst=1
Asia/Baku  Thu Aug 29 19:59:59 1991 UTC = Thu Aug 29 23:59:59 1991 BAKST
isdst=1
Asia/Baku  Thu Aug 29 20:00:00 1991 UTC = Fri Aug 30 00:00:00 1991 AZST
isdst=1
Asia/Baku  Sat Sep 28 22:59:59 1991 UTC = Sun Sep 29 02:59:59 1991 AZST
isdst=1
Asia/Baku  Sat Sep 28 23:00:00 1991 UTC = Sun Sep 29 02:00:00 1991 AZT
isdst=0
Asia/Baku  Sat Mar 28 19:59:59 1992 UTC = Sat Mar 28 22:59:59 1992 AZT
isdst=0
Asia/Baku  Sat Mar 28 20:00:00 1992 UTC = Sun Mar 29 00:00:00 1992 AZST
isdst=1
Asia/Baku  Sat Sep 26 18:59:59 1992 UTC = Sat Sep 26 22:59:59 1992 AZST
isdst=1
Asia/Baku  Sat Sep 26 19:00:00 1992 UTC = Sat Sep 26 22:00:00 1992 AZT
isdst=0
Asia/Baku  Sat Sep 26 22:59:59 1992 UTC = Sun Sep 27 01:59:59 1992 AZT
isdst=0
Asia/Baku  Sat Sep 26 23:00:00 1992 UTC = Sun Sep 27 03:00:00 1992 AZT
isdst=0
Asia/Baku  Sun Dec 31 19:59:59 1995 UTC = Sun Dec 31 23:59:59 1995 AZT
isdst=0
Asia/Baku  Sun Dec 31 20:00:00 1995 UTC = Mon Jan  1 01:00:00 1996 AZST
isdst=1
Asia/Baku  Sun Oct 27 00:59:59 1996 UTC = Sun Oct 27 05:59:59 1996 AZST
isdst=1
Asia/Baku  Sun Oct 27 01:00:00 1996 UTC = Sun Oct 27 05:00:00 1996 AZT
isdst=0
Asia/Baku  Sat Mar 29 20:59:59 1997 UTC = Sun Mar 30 00:59:59 1997 AZT
isdst=0
Asia/Baku  Sat Mar 29 21:00:00 1997 UTC = Sun Mar 30 02:00:00 1997 AZST
isdst=1
Asia/Baku  Sat Oct 25 19:59:59 1997 UTC = Sun Oct 26 00:59:59 1997 AZST
isdst=1
Asia/Baku  Sat Oct 25 20:00:00 1997 UTC = Sun Oct 26 00:00:00 1997 AZT
isdst=0
...