There is a glitch in GUI when trying to switch between subscriptions with the option "Open hosting operations in Server Administration Panel" disabled.
Below are exact steps to reproduce the issue:
Plesk Control panel->Tools and Utilities->Interface Managementthat "Service Provider view" mode is enabled and option" Open hosting operations in Server Administration Panel" is NOT selected.
Create 2 subscriptions under the same customer, for example under admin: domain1.com and domain2.com
domain1.com->backup manager->Personal FTP Repository Settingsand configure FTP backup settings for subscription
Now switch to different subscription clicking on drop down menu on the top of window under webspace option, please see screenshot
You should appear under backup settings of other subscription
Click on "Personal FTP Repository Settings" and you will see FTP backup settings of first subscription
The issue is fixed in Plesk 11.5 completely.
This is a program issue #PPPM-703. The issue persists in Plesk 10.4, 11.0.9. Completely fixed in Plesk 11.5