[rsadani]

In that case, The later solution suggested by rvhaaster should work.

One more option could be to
1. Define a Service provider profile for this carrier
2. Uncheck the Compatible flag on the Service provider profile.
3. Assign this service provider profile in Constraints tab on order release (you can use some form of automation for this)
The service provider will then be excluded for Planning process.

Thanks
Ravindra