"AddressPool" is registered for version "metallb.io/v1alpha1" error during MetalLB operator upgrade

Issue

• When initiating the update of the MetalLB-Operator on the cluster, the operator remains in a "pending" status, and the following error is encountered.

error validating existing CRs against new CRD's schema for "addresspools.metallb.io": error listing resources in GroupVersionResource schema.GroupVersionResource{Group:"metallb.io", Version:"v1alpha1", Resource:"addresspools"}: conversion webhook for metallb.io/v1beta1, Kind=AddressPool failed: no kind "AddressPool" is registered for version "metallb.io/v1alpha1" in scheme "/metallb/internal/k8s/k8s.go:59"