Scaling
Relay automatically scales to meet user demands without affecting costs at all. Unity takes full responsibility for maximizing CPU and network usage by performing automatic scaling for users.
Note: There is no logic to reroute allocations to nearby regions with capacity. If there isn’t enough capacity to fulfill a request at the time of an allocation, you must resend the allocation request.
The primary symptom of this occurring is a failed allocation request, in which case, you will need to retry the request. You can retry the request with the same region (there might be more capacity by that point) or with a different nearby region.