Pod disruption budget is typically used to quantify application (composed of multiple pods) disruption during a node drain, which occurs during OCP upgrades.  If a PDB exists, it can block a node drain and block OCP updates, and if PDB condition is not satisfied, the block could possibly be “forever.”

If possible, offer a warning message or an admin acknowledgement that if PDB exists, the update may get disrupted.

Add this to the Preparing to update OCP documentation about watching out for PDBs and its impact.  Refer to https://kubernetes.io/docs/tasks/run-application/configure-pdb/ for best practices on how to setup pod disruption budgets.