Hi
In the UK you can dial 141 before a number to block call id - so you could create a route pattern with this as a prefix digits entry, and put it in a partition/calling search space that is only applied to your Principals number.
Otherwise you could set the External Phone Number Mask on his DN to be another number (i.e. your main switchboard number).
Both these will affect both instances of your shared line though.
If you want it to affect only his instance of the line you would need to set the CSS mentioned above with the alternate route pattern on his phone (as opposed to the line), then set the standard CSS on the other phone that shares the line. Don't set a CSS on the line as well as this will have a higher priority.
Aaron
Aaron
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