Due to limitations of OLM and CRDs being deployed cluster-wide, we do not support different versions of the Data Grid Operator being deployed on the same cluster. However, this is not currently stated in our documentation upstream or downstream. We should make it clear to users that the best practice is to deploy the Operator cluster-wide and for users to use `spec.version` in their Infinispan CRs to control upgrading of Infinispan server versions.

JDG-7683 added these details to the release notes of the Operator, however this issue is applicable to all operator versions and so it should be included in our general documentation both upstream and downstream.

Adding the instructions to the Operator Installation Guide will ensure that both upstream and downstream users are aware of these limitations. Once the documentation has been updated upstream as part of Infinispan 16, this will automatically be included in the DG Operator 8.6.0.CSV documentation.