This method allows you to change the overflow of a failover group.
| Parameter | Description |
| Overflow | boolean (0/1) |
| OverflowMethod | “string” |
| GlobalMaxClients | “string” |
| IsTrafficUnavailable | boolean (true/false) |
| IsTrafficSticky | boolean (true/false) |
| TrafficStickyMinutes | “string” |