"Plan for the worst, but hope for the best." No, there shouldn't in theory be any issues enabling the Infra VLAN on an AEP. All it does it allow your infra VLAN to the allowed VLANs on the related interfaces. Similar to any EPG static path map or EPG VMM domain domain binding would. The difference is an AEP change can potentially affect far more interfaces than a single EPG mapping/binding.
Some things to check:
- Ensure the infra VLAN ID is not used by anything else in your environment (other than ACI), nor is it a reserved VLAN on any platforms between the Leaf and your AVE host (in cases where there may be intermediate switches).
- Ensure there's no overlap in your Dynamic & static VLAN pools (this is a general best practice to avoid issues)
Regardless if a change should not impact operations, its always best to perform any changes which involve active workloads during a maintenance window. Taking the cautious road will avoid any woulda-shoulda-coulda types of explanations to your users later.
Robert