Is this happening on cloud or a self-hosted deployment? If it is on cloud, would you give me permission to access your workflow through a support account to help debug the issue?
@andrei I've just tried again, the issue seems to be fixed (CPU back to <2% on Arc). However, keep in mind that the workflow is not in the same state that it was when the bug occurred.
I will contact you by email/here in case of sudden new CPU consumption.