Hi Srikanth,
Keeping the routes aside for the time being..
Once if a transport request is released a data file and cofile will be created in usr/sap/trans directory which is a mount point for a transport group so, the change request can be picked up by all the systems in the group.
In your case QST is a sandbox or pre production system. so, the change request will be seen in QST buffer as well.
Thanks,
Pavan