[IPI on HW provided by IBM cloud] Upgrade for nodes added after updating to 4.9.0-rc.1 fails as nodes boot into ironic discovery

Description of problem:
Installing a cluster with 4.9.0-rc.0, adding a new node after installation and upgrading the cluster to 4.9.0-rc.1 works. However adding then new nodes and upgrading the cluster to 4.9.0-rc.3 fails for the new added nodes added after upgrading to rc1 as they get beack into ironic discovery when rebooted by the upgrade

Version-Release number of selected component (if applicable):
4.9.0-rc.1

How reproducible:

Steps to Reproduce:
1. set up IPI HW cluster on IBM cloud following https://deploy-preview-36529--osdocs.netlify.app/openshift-enterprise/latest/installing/installing_ibm_cloud/install-ibm-cloud-installing-on-ibm-cloud.html

2. confirm cluster is up and running with 3 maters and 2 nodes (dmoessne-m0,dmoessne-m1,dmoessne-m2,dmoessne-w0,dmoessne-w1) up, co are all fine

3. add a 3rd worker (dmoessne-w2) following https://deploy-preview-36529--osdocs.netlify.app/openshift-enterprise/latest/installing/installing_bare_metal_ipi/ipi-install-expanding-the-cluster.html

4. Confirm that 3rd (dmoessne-w2) worker was added successfully (ready)

5. upgrade to 4.9.0-rc.1

6 verify upgrade was successful (oc get co, oc adm upgrade, oc get nodes,mcp ..)

7. add additional nodes and confirm they have been successfully added (dmoessne-w3,dmoessne-w4,dmoessne-w5)

8. set in mcp worker maxUnavailable to 3 (that is just to avoid getting stuck in case dmoessne-w3,dmoessne-w4,dmoessne-w5 are choosen as a start for worker upgrade )

9. upgrade to 4.9.0-rc.3

Actual results:
masters and and workes added prior to upgrade to rc1 are successfully updated (dmoessne-m0,dmoessne-m1,dmoessne-m2,dmoessne-w0,dmoessne-w1,dmoessne-w2)
however, workers added after upgrading to rc1 (dmoessne-w3,dmoessne-w4,dmoessne-w5) get stuck and checking their console shows that they are back in ironic inspection without coming back (DHCP boot is still enabled for them despite being provisioned)

Expected results:
all nodes get updated successfully/ironic dhcp boot is disabled for successfully provisioned nodes

Additional info:

Disabling provisioning, i.e.

1. oc edit provisioning
   ~~~
   [...]
   spec:
   preProvisioningOSDownloadURLs: {}
   provisioningNetwork: Disabled
   provisioningOSDownloadURL: http://<IP>:8080/rhcos-49.84.202107010027-0-openstack.x86_64.qcow2.gz?sha256=00cb56c8711686255744646394e22a8ca5f27e059016f6758f14388e5a0a14cb
   status:

[...]
~~~

and powercycling the nodes let's the cluster upgrade.
Enabling provisioner again and rebooting one of the affected nodes immediately brings them back in iroic discovery