Previously, CBR was disabled when planning for SBE, due to a number of unresolved issues. This led to CBR becoming "engine aware" with several branches taken only if SBE or Classic.

With the move to deferred engine selection, the decision of which engine to use will occur after CBR.

Currently deferred engine selection "lies" to CBR by claiming to be classic to allow CBR to run.

This should be cleaned up; CBR should not need to be engine aware, and in the "legacy" SBE path, CBR should not be invoked.