Why does the Tivoli Storage Management links like /usr/lib64/libApiTSM64.so and /usr/lib64/libtsmxerces-c.so.28 get deleted after system update?

Issue

• Had installed Tivoli Storage Management on top of Red Hat Enterprise Linux 6.6 machine, and links created by the packages were as follows.

[root@localhost Tivoli]# ls -l /usr/lib64/libApiTSM64.so /usr/lib64/libtsmxerces-c.so.28 /usr/lib64/libtsmxerces-depdom.so.28 /usr/lib64/libxmlutil-7.1.1.0.so
lrwxrwxrwx 1 root bin 52 Feb  4 11:21 /usr/lib64/libApiTSM64.so -> ../../opt/tivoli/tsm/client/api/bin64/libApiTSM64.so
lrwxrwxrwx 1 root bin 60 Feb  4 11:21 /usr/lib64/libtsmxerces-c.so.28 -> ../../opt/tivoli/tsm/client/api/bin64/libtsmxerces-c.so.28.0
lrwxrwxrwx 1 root bin 65 Feb  4 11:21 /usr/lib64/libtsmxerces-depdom.so.28 -> ../../opt/tivoli/tsm/client/api/bin64/libtsmxerces-depdom.so.28.0
lrwxrwxrwx 1 root bin 59 Feb  4 11:21 /usr/lib64/libxmlutil-7.1.1.0.so -> ../../opt/tivoli/tsm/client/api/bin64/libxmlutil-7.1.1.0.so

• Post update, the links were deleted.

[root@localhost ~]# ls -l /usr/lib64/libApiTSM64.so /usr/lib64/libtsmxerces-c.so.28 /usr/lib64/libtsmxerces-depdom.so.28 /usr/lib64/libxmlutil-7.1.1.0.so
ls: cannot access /usr/lib64/libtsmxerces-c.so.28: No such file or directory
ls: cannot access /usr/lib64/libtsmxerces-depdom.so.28: No such file or directory
lrwxrwxrwx 1 root bin 52 Feb  8 11:36 /usr/lib64/libApiTSM64.so -> ../../opt/tivoli/tsm/client/api/bin64/libApiTSM64.so
lrwxrwxrwx 1 root bin 59 Feb  8 11:36 /usr/lib64/libxmlutil-7.1.1.0.so -> ../../opt/tivoli/tsm/client/api/bin64/libxmlutil-7.1.1.0.so

• During the update, the storage mount /opt/tivoli was unmounted and then the update was performed.
• Why were these links deleted by Red Hat Enterprise Linux 6.7 update? What's the cause?