IRQs not moving to reserved CPU set when using the Performance Addon Operator to isolate CPUs in Red Hat OpenShift Container Platform 4.6 and 4.7

Issue

Not all IRQs are moving to the reserved CPU set from the isolated CPU set when using the Performance Addon Operator to isolate CPUs in Red Hat OpenShift Container Platform 4.6 and 4.7.

Option_1:

  cpu:
    isolated: 2-47
    reserved: 0-1

Option_2:

  cpu:
    isolated: 2-47
    balanceIsolated: false
    reserved: 0-1

When enabling the Performance Addon Operator (PAO) on a single socket node, one can see that many of the IRQs are not moved to the reserved CPUs.
This happens using Option_1 or Option_2 configs as described above.